CN115191380B

CN115191380B - Coral culture method, system and product thereof

Info

Publication number: CN115191380B
Application number: CN202210303957.8A
Authority: CN
Inventors: 沈儀仁
Original assignee: Popai Marine Biotechnology Co ltd
Current assignee: Popai Marine Biotechnology Co ltd
Priority date: 2021-04-07
Filing date: 2022-03-25
Publication date: 2024-06-07
Anticipated expiration: 2042-03-25
Also published as: CN115191380A; TW202239325A; TWI807721B

Abstract

The invention provides a coral culture method, which provides stable optimal growth environment and nutrition for small-hydroid hard coral by monitoring the seawater environment in a water tank, so that the small-hydroid hard coral can be produced in mass; the invention also provides a coral culture system and a coral product, and the coral culture method is implemented by the coral culture system, so that the obtained coral product has stable and excellent quality and is not polluted by heavy metals.

Description

Coral culture method, system and product thereof

Technical Field

The invention relates to a coral culture method, in particular to an indoor coral culture method; the invention also relates to a coral culture system and a coral product.

Background

The development of regenerative medicine is rapid, and the coral bone structure has a porous structure similar to human bone, so the coral bone is an emerging natural biological material and has wide medical application in the future.

However, in today where industrial development and commercial activities are frequent, due to the increasingly serious greenhouse effect, not only the global climate is drastically changed to cause the ecological environment to be deteriorated, but also the factory waste water and frequent oil leakage of ships are more direct causes of coral death.

In open sea, corals are difficult to recuperate once whitened and die, natural ecological protection focuses on ecological diversity, and besides being unsuitable for cultivating a single species, ecological influence factors are numerous and can interact, so that development of an indoor cultivation method of the corals is urgently needed.

Disclosure of Invention

The invention provides a coral culture method which can be used for large-scale culture of small-hydroid hard coral (Small Polyp Stony Corals), namely SPS hard coral commonly known as SPS hard coral. The invention also provides a coral culture system and a coral product.

The cultivation of the invention refers to the asexual reproduction of the Hdrozoon hard coral for hyperplasia and growth, but does not include sexual reproduction. In addition, the whole coral culture method is indoor culture, belongs to an artificial culture method, and does not use wild coral.

In order to achieve the above purpose, the invention provides a coral culture method, comprising the following steps: providing a water tank, wherein the water tank contains seawater, and the seawater comprises calcium ions and magnesium ions; an inoculation step comprising: placing a coral on a base, wherein the base is placed in the water tank; a culturing step, comprising: maintaining the pH of the seawater at 7.8 to 8.8, the salinity at 29ppt (parts per thousand) to 37ppt, the alkalinity at 7dKH to 10dKH, the temperature at 20 ℃ to 26 ℃, the concentration of calcium ions at 430ppm to 500ppm, and the concentration of magnesium ions at 1290ppm to 1500ppm; a feeding step, comprising: providing the coral-bait; an illumination step comprising: providing the coral-light source for at least 6 hours per day; and a decontamination step comprising removing froth from the seawater and filtering the seawater, wherein the filtered water volume is at least 2.6 volume percent per minute based on the total volume of seawater in the tank; wherein the coral is Hydra minor hard coral (Small Polyp Stony Corals).

The invention provides the stable optimal growth environment of the hard coral with the small hydroids by monitoring the seawater environment in the water tank and provides a light source so as to facilitate photosynthesis of symbiotic algae and provide nutrients for the hard coral with the small hydroids to enable the hard coral with the small hydroids to stably grow and form coral bones. In addition, the filtering is helpful for purifying the seawater quality, and the removal of floating foam can reduce the content of organic matters such as protein, amino acid and the like in the seawater, so as to avoid death of the small hydroid hard coral caused by water quality deterioration.

The coral bone of the invention is calcium carbonate coral bone.

The term "comprising" as used herein may be replaced by a closed-form or a semi-closed-form, such as: the term "comprising" may refer to "consisting of …" or "consisting essentially of. This description is not intended to limit the scope of the claims unless specifically modified.

The seawater can be natural seawater or artificial seawater prepared by imitating natural seawater salt; preferably, the pH of the seawater is maintained at 8.0 to 8.6; more preferably, the pH of the seawater is maintained at 8.2 to 8.4. Preferably, the salinity of the seawater is maintained at 29.5ppt to 34ppt; more preferably, the salinity of the seawater is maintained at 29.7ppt to 32ppt. Preferably, the alkalinity of the seawater is maintained at 8.0dKH to 9.0dKH; more preferably, the alkalinity of the seawater is maintained at 8.2dKH to 8.8dKH; still more preferably, the alkalinity of the seawater is maintained at 8.4dKH to 8.6dKH. Preferably, the temperature of the seawater is maintained at 22 ℃ to 25.5 ℃; more preferably, the temperature of the seawater is maintained at 23 ℃ to 25 ℃.

In one embodiment, the seawater has a depth of 10 cm to 50 cm; preferably, the depth of the seawater is 30 cm to 40 cm; more preferably, the seawater is 35 cm deep. The coral can stably grow and is favorable for harvesting by adopting the culture method of the invention even though the seawater environment of shallow vat culture is greatly changed.

Preferably, the coral is selected from the group consisting of: beautiful axial hole coral (Acropora formosa), noble axial hole coral (Acropora nobilis), simple axial hole coral (Acropora austere), gorgon axial hole coral (Acropora valenciennesi), forked axial hole coral (Acropora pulchra), small She Zhoukong coral (Acropora microphtha), intermediate axial hole coral (Acropora intermedia) and bergamot axial hole coral (Acropora florida), but are not limited thereto.

The homologous and heterogeneous name of the beautiful shaft hole coral is Acropora muricata.

The coral of different species is cultivated in separate tanks or substantially in separate tanks, wherein the optimal growth conditions of the cultivation of a single species are the same, but the nutrition demand consumption and the waste discharge are the same, so that the seawater environment is easy to change rapidly, and the cultivation threshold is relatively high; if different kinds of corals are cultivated in the same water tank together, although the different species take the required seawater environment is easy to maintain constant, partial corals are easy to remove algae and whiten; essentially zoned cultivation avoids competition for growth space for different species.

Preferably, the coral is a coral segment comprising a calcium carbonate segment and a coral worm. Based on the fact that coral-deficient symbiotic algae will whiten and die, the coral worms of the present invention contain symbiotic algae.

In one embodiment, the length of the calcium carbonate fragment is 0.2 cm to 4 cm; preferably, the calcium carbonate fragments are in a particle form, i.e. the calcium carbonate fragments are calcium carbonate particles, and the particle size of the calcium carbonate particles is 0.2 cm to 0.5 cm; more preferably, the calcium carbonate particles have a particle size of 0.3 cm to 0.4 cm.

The coral segment may be punctiform and is obtained from any part of the parent coral strain; or the coral segment is a segment and is a broken branch of the parent strain of coral.

When the calcium carbonate particles are smaller, the survival probability of the coral is lower in the early stage after inoculation, and the seawater environment is accurately regulated, so that the size of the calcium carbonate particles can be greatly reduced, and meanwhile, the coral fragments can be still ensured to grow smoothly.

Preferably, the coral segments have a density of 50 to 60 coral segments per square meter.

Preferably, the filtered water amount per minute is 2.6 to 8.6 volume percent per minute based on the total volume of the seawater in the water tank; more preferably, the amount of filtered water per minute is 4.5 to 6.6 volume percent per minute; still more preferably, the amount of filtered water per minute is from 5 to 6.1 volume percent. The total volume of the seawater in the water tank refers to the volume of the seawater actually contained in the water tank, and the water tank is simultaneously used for containing small-hydroid hard coral to provide a growing environment, so that the total volume of the seawater in the water tank does not account for the seawater in other tanks such as pipelines, filter tanks or water storage tanks. The invention provides a sufficient percentage of filtered water, which not only can ensure the water quality, but also can ensure the flow of seawater in the water tank, and can prevent coral death.

SPS hard coral generally only survives in low nutrient salt environments, i.e., calcium ion concentrations below 420ppm and magnesium ion concentrations below 1260ppm, otherwise albinism death is readily observed; by regulating the water filtering amount, the SPS hard coral cultivated in high density can grow and grow fast in high concentration calcium ion and magnesium ion environment.

Preferably, the base comprises a ceramic base plate or a cement plate; in one embodiment, the ceramic substrate or cement tray is cylindrical.

According to the invention, the cylindrical ceramic basal disc is adopted, so that the attachment of algae can be reduced, and other algae can be prevented from expelling the growth space of coral worms. The ceramic substrate has fine three-dimensional holes, is beneficial to the growth of nitrifying bacteria, aerobic bacteria and facultative anaerobic bacteria, and is beneficial to reducing nitrate, nitrite and phosphate in seawater.

Preferably, the seawater includes phosphate, nitrate and nitrite, and the phosphate concentration is maintained at greater than or equal to 0ppm and less than 0.03ppm, the nitrate concentration is maintained at greater than or equal to 0ppm and less than 0.5ppm, and the nitrite concentration is maintained at greater than or equal to 0ppm and less than 0.1ppm. The term "0 ppm" means that the sample was not detected.

The above-mentioned phosphate, nitrate and nitrite concentrations are too high, and the algae will excessively proliferate, thereby being unfavorable for maintaining the cleanliness of water quality.

Preferably, the concentration of the calcium ions is maintained at 450ppm to 480ppm.

Preferably, the concentration of the magnesium ions is maintained at 1370ppm to 1420ppm.

According to the invention, the specific content of calcium ions and magnesium ions and alkalinity can help the small hydroids hard coral secrete calcium carbonate to form bone. If the concentration of calcium ions, magnesium ions and alkalinity is too high, crystals are easy to form in the water tank; if the concentration is too low, the coral color will become dark and die.

Preferably, the illumination time is 9 to 13 hours per day; more preferably, the illumination time is 10 to 12 hours per day.

The above-mentioned illumination time may be continuously performed.

In one embodiment, the seawater is monitored from 5 to 12 times per day; preferably, the seawater is monitored 8 to 12 times per day, for example: 10 times.

Preferably, the light source is selected from the group consisting of: 2800K to 3800K white light, 5000K to 6500K white light, 425nm to 435nm blue light and 445nm to 470nm blue light.

According to the invention, the light source or the combination thereof can control the quantity of the hydroids and the symbiotic algae, so that the growth rate of the hard coral with the hydroids can be further controlled by the collocation of different light sources, and the hard coral with the hydroids is evenly distributed.

In one aspect, the feeding step is at a frequency of 8 to 15 feeds per day; preferably, the feeding step is carried out at a frequency of 1 to 3 times per week.

Preferably, the bait comprises any one or a combination of rotifers and paramecium. The rotifer provided by the invention can make bones of coral stronger.

In one embodiment, the wheel worm comprises any one or a combination of small wheel worm (S-type) rotifers, super small wheel worm (SS-type) rotifers.

The length of the small wheel worm is 100 micrometers to 210 micrometers; preferably, the length of the small wheel worm is 100 to 120 microns. The length of the microminiature wheel is 90 to 110 microns.

In one embodiment, the average length of the small wheel is 160 microns.

In one aspect, the rotifer comprises any one of, or a combination of, a rotifer (Brachionus rotundiformis), an abaricus rotifer (Brachionus ibericus).

The hard coral has a body and a branch, and according to the present invention, the vertical height of the whole plant of the hard coral may be increased by 0.5 cm to 0.8 cm per month, the length of the branch may be increased by 0.3 cm to 1 cm per month, the diameter of the body of the hard coral may be increased by 0.05 cm to 0.15 cm per month, and the diameter of the branch may be increased by 0.05 cm to 0.8 cm per month. The branches of the small hydroids hard coral are finer, so the maximum growth rate can be greater than the maximum growth rate of the vertical height of the whole plant.

Preferably, after culturing the coral segment for 500-600 days, a whole plant of coral is obtained; wherein the vertical height of the whole plant coral is 12 cm to 20 cm, the length of the branches is 5 cm to 15 cm, the diameter of the main body is 1.5 cm to 3.5 cm, and the diameter of the branches is 0.6 cm to 1.5 cm; more preferably, the vertical height of the body of the whole plant coral is 15 cm to 20 cm, the length of the branches is 6 cm to 15 cm, the diameter of the body is 1.6 cm to 3.5 cm, and the diameter of the branches is 0.8 cm to 1.5 cm.

The invention also provides a coral culture system, which comprises: a seawater comprising calcium ions and magnesium ions, wherein the seawater is maintained at a pH of 7.8 to 8.8, a salinity of 29ppt (parts per thousand) to 37ppt, a alkalinity of 7dKH to 10dKH, a temperature of 20 ℃ to 26 ℃, a concentration of the calcium ions of 430ppm to 500ppm, and a concentration of the magnesium ions of 1290ppm to 1500ppm; the water tank is used for containing the seawater, at least one base is arranged on the bottom surface of the water tank and used for containing a coral, and the filtered water amount is at least 2.6 volume percent per minute based on the total volume of the seawater in the water tank; a light source module for providing the coral light for at least 6 hours; a water purifying module for filtering the seawater; a defoaming module for removing the floating foam of the seawater; a pure water supply module for supplying pure water to the seawater and having a water supply port; the water storage tank is provided with a water inlet and a water outlet; wherein the water inlet and the water outlet are respectively communicated with the water tank and the water storage tank, and the water supply port is communicated with the pure water supply module and the water storage tank.

The coral culture system adopts the coral culture method.

Preferably, each base individually accommodates a coral.

Preferably, the light source module is disposed 40 cm to 150 cm above the water level of the seawater.

Preferably, the water storage tank is arranged below the bottom of the water tank.

Preferably, the pure water supply module further comprises a pure water inlet control module for opening or closing the water supply port; more preferably, the water supply port is adjacent to the water outlet.

The pure water supply module can be an RO cold water purifier; the pure water may be reverse osmosis water.

Preferably, the water purifying module is accommodated in the water storage tank.

Preferably, the coral, seawater, base, light source module, illumination time and filtered water are the same as those of the coral, seawater, base, light source, illumination time and filtered water in the coral culture method.

Preferably, the water purification module comprises biochemical cotton, ceramic rings, filter cotton, coral filter stones and living stone coral reefs.

The biochemical cotton can be used for culturing nitrifying bacteria, aerobic bacteria and facultative anaerobic bacteria and strengthening the absorption of harmful substances; the ceramic ring can also provide excellent propagation living environment for nitrifying bacteria, aerobic bacteria and facultative anaerobic bacteria; the filter cotton is a main filter cotton of the water purifying module and is used for filtering feces and impurities generated by coral, fish and algae in the filter tank; the coral filter stone can balance calcium content and filter seawater; the living Dan Shanhu reef provides a stable ecological environment for microorganisms, and can generate a biological chain for the growth of nitrifying bacteria, aerobic bacteria and facultative anaerobic bacteria, reduce the content of nitrate and phosphate, and release organic matters for coral and other microorganisms.

Preferably, the water storage volume ratio of the water tank to the water storage tank is 4 to 5 to 1. According to the invention, the water storage tank is provided with the water purifying module, so that the water purifying module can purify the seawater, and the water quality can be adjusted in real time by providing a sufficient amount of clean seawater, so that the yield and quality of the small-hydroid hard coral are ensured.

The present invention further provides a coral article comprising a calcium component and a magnesium component and having a plurality of through-holes; wherein the calcium component comprises calcium and the magnesium component comprises magnesium, and the content of calcium is more than or equal to 95 weight percent, the content of magnesium is less than or equal to 1 weight percent, and the metal element comprises calcium, magnesium, potassium, iron and sodium, and the non-metal element comprises phosphorus, based on the total weight of the metal element and the non-metal element contained in the coral product.

In one embodiment, the metallic element comprises lead, cadmium, mercury, copper, calcium, magnesium, potassium, zinc, iron, manganese, and sodium, and the nonmetallic element comprises arsenic, phosphorus, and selenium.

In one embodiment, the metallic element comprises lead, cadmium, mercury, copper, calcium, magnesium, potassium, zinc, iron, manganese, and sodium, and the nonmetallic element comprises silicon, arsenic, phosphorus, and selenium.

Since the listed elements are the detection items, the denominator of the total amount calculation is included, and the coral article of the present invention does not necessarily include each of the listed elements.

Preferably, the calcium content is 98 to 99 weight percent based on the total weight of the metal and non-metal elements contained in the coral article.

Preferably, the content of magnesium is 0.15 to 0.35 weight percent based on the total weight of metal and non-metal elements contained in the coral article; preferably, the magnesium is present in an amount of 0.19 to 0.35 weight percent. More preferably, the magnesium is present in an amount of 0.2 to 0.22 weight percent, or 0.3 to 0.35 weight percent.

In one embodiment, the coral article further comprises a phosphorus component, and the phosphorus component comprises phosphorus in an amount of 0.005 wt.% to 0.010 wt.% based on the total weight of the metal element and the non-metal element contained in the coral article; preferably, the phosphorus content is 0.0065 to 0.008 weight percent. More preferably, the phosphorus content is from 0.0065 to 0.0076 weight percent, for example: 0.0065 weight percent, 0.0067 weight percent, 0.0070 weight percent, 0.0072 weight percent, 0.0075 weight percent, or 0.0076 weight percent.

In one embodiment, the coral article further comprises a potassium component, and the potassium component comprises potassium in an amount of 0.015 wt.% to 0.030 wt.% based on the total weight of the metallic element and the non-metallic element contained in the coral article. Preferably, the potassium content is 0.017 to 0.030 weight percent; more preferably, the potassium content is 0.019 to 0.021 weight percent or 0.027 to 0.028 weight percent.

In one embodiment, the coral article further comprises an iron component, and the iron component comprises iron and is present in an amount of 0.002 wt% to 0.11 wt% based on the total weight of the metal element and the non-metal element present in the coral article. Preferably, the iron content is 0.0025 to 0.1 weight percent; more preferably, the iron content is 0.0030 to 0.0034 weight percent, or 0.095 to 0.098 weight percent.

In one embodiment, the coral article further comprises a sodium component, and the sodium component comprises sodium and is present in an amount of 0.5 wt.% to 2 wt.% based on the total weight of the metal element and the non-metal element present in the coral article; preferably, the sodium content is 1.0 to 1.4 weight percent; more preferably, the sodium content is 1.0 to 1.2 weight percent.

In one embodiment, the coral article further comprises a silicon component, and the silicon component comprises silicon and is present in an amount of 0.05 wt.% to 0.15 wt.% based on the total weight of the metal element and the non-metal element present in the coral article; preferably, the silicon content is 0.07 to 0.12 weight percent; more preferably, the silicon content is 0.09 to 0.1 weight percent.

In one embodiment, the coral product contains arsenic, lead, cadmium, mercury, copper, zinc, manganese, and selenium in amounts that are each undetected or less than 0.001 wt.% to 0 wt.%; more preferably, the arsenic, lead, cadmium, mercury, copper, zinc, manganese and selenium are each present in an amount of less than 0.0007 to 0 weight percent.

In one embodiment, the total weight of calcium, sodium, and magnesium is greater than or equal to 99.5 weight percent based on the total weight of the metallic and non-metallic elements contained in the coral article. Preferably, the phosphorus content is less than or equal to 0.010 weight percent; the content of potassium is less than or equal to 0.030 weight percent; the content of iron is less than or equal to 0.11 weight percent; and/or the silicon content is less than or equal to 0.15 weight percent. More preferably, the silicon content is less than or equal to 0.1 weight percent.

The calcium component may be calcium carbonate (CaCO ₃).

The magnesium component may be magnesium carbonate (MgCO ₃).

In one embodiment, the coral product is obtained by processing from a hard coral (Small Polyp Stony Corals) that is a Hydra minor. The processing may refer to mechanically changing the shape and/or chemically changing the composition or properties.

In one embodiment, the coral article is a block. The block material is a single object and is not formed by splicing or connecting a plurality of mutually independent objects. Preferably, the coral article is a bone block. More preferably, the bone pieces comprise substantially calcium carbonate.

Preferably, the coral product is a geometric body, and each of the coral product has a length, a width, and a height of 0.2cm to 12 cm.

In one embodiment, the geometric body is a cuboid and has a length of 0.3 cm to 5 cm; a width of 0.2 cm to 3.5 cm; and a height of 0.2 cm to 3.5 cm.

In another embodiment, the geometric shapes are cubes and each have a length, width and height of 0.2 cm to 3.5 cm.

In yet another aspect, the geometric body is a sphere and has a diameter of 0.2 cm to 3.5 cm.

In yet another embodiment, the geometry is a cylinder and has a diameter of 0.2 cm to 3.5 cm and a height of 0.5 cm to 7 cm, for example: 5 cm.

Preferably, the coral product is in the form of particles having a particle size of at least 250 microns or greater than 2000 microns; preferably 250 microns to 5000 microns, for example: 250 microns, 500 microns, 1000 microns, 2000 microns, 3000 microns, 4000 microns or 5000 microns.

The coral strain is obtained by processing coral bones of coral obtained by the coral culture method or culture system.

Preferably, the through hole is provided with a hole positioned on the surface of the coral bone and a channel positioned in the coral bone, and the hole is communicated with the channel. More preferably, the channels are plural and communicate with each other to form a complex interconnect. Still more preferably, the through-holes are formed during coral growth, and are formed mechanically or chemically after coral bones are not obtained.

In one embodiment, the coral article has an average compressive strength of 50 kilograms force (kgf) to 200 kilograms force. Preferably, the coral article has an average compressive strength of 90 kg to 150 kg, for example: 90 kg force, 100 kg force, 110 kg force, 120 kg force, 130 kg force, 140 kg force or 150 kg force. More preferably, the coral article has an average compressive strength of 95 kg force (kgf) to 110 kg force. The average compressive strength of the invention is the average maximum compressive load.

In one embodiment, the average compressive strength is performed in accordance with the specifications of ISO 13175-3 (2012). Preferably, the coral article has an average diameter of 10.1 millimeters (mm), an average height of 15.1 mm, a test speed of 0.50 millimeters per minute (mm/min), a steel ball diameter of 12.7 mm and/or an instrument of Universal testing machine (Universal TESTING MACHINE, trade name: MTS), for example: criterion C43 universal tester.

In one embodiment, the coral article has a via average diameter of 0.5 microns to 1.7 microns. Preferably, the coral article has a through-hole average diameter of 0.7 microns to 1.2 microns, for example: 0.7 microns, 0.8 microns, 0.9 microns, 1.0 microns, 1.1 microns, or 1.2 microns. More preferably, the coral article has a through-hole average diameter of 0.85 microns to 1.05 microns.

In one aspect, the via average diameter is performed in accordance with the specifications of ISO 13175-3 (2012). Preferably, the coral article is in the form of a granulate, for example: powder, and the diameter of the through hole was measured in a 4000 times magnified field of view. In other words, after 4000 times of amplification, it cannot be determined that it is a through hole, and it is not measured.

In one embodiment, the coral article has an average spacing between the centers of two through-holes of 5 microns to 10 microns. Preferably, the coral article has an average spacing between the centers of the two through holes of 6 microns to 9 microns, for example: 6 microns, 7 microns, 8 microns or 9 microns. More preferably, the coral article has an average spacing between the centers of the two through holes of 6.8 microns to 7.6 microns.

In one embodiment, the coral article has a standard deviation of the spacing between the centers of the two holes that is less than 1-2 of the average spacing between the centers of the two holes. Preferably, the standard deviation of the spacing between the centers of two through holes of the coral article is greater than 0 and less than 1/3 of the average spacing between the centers of two through holes, for example: less than 1/4 or 1/5 of the average spacing between the centers of the two vias.

In one embodiment, the coral article is in the form of particles, for example, when the average spacing between the centers of the two holes of the coral article is measured: powder, and the diameter of the through hole was measured in a 4000 times magnified field of view. In other words, after 4000 times of amplification, it cannot be determined as a through hole and is not measured. Preferably, in the 4000 times enlarged view, 10 adjacent through holes are selected, and the diameter of each through hole is larger than 0 micron and smaller than or equal to 5 microns.

In one embodiment, the coral article has a Crystallinity (CRYSTALLINITY) of 79% to 81%, and an amorphous (Amorphous) of 19% to 21%. Preferably, the coral product has a crystallinity of 79.9% and an amorphism of 20.1%, so the coral product of the present invention has a high proportion of crystals.

The small-hydroid hard coral cultured by the method grows in an indoor stable circulatory system, so that various environmental changes, pollution and infection in an outdoor open sea area are avoided, the sizes, densities and components of the obtained coral bones can be accurately controlled and stabilized, and the problems that the outdoor natural coral bones possibly contain heavy metal components, and the pore sizes of the interconnection through holes are different, the pore distribution is uneven and cavitation is avoided. In other words, the coral skeleton structure and composition of the small-hydroid hard coral of the present invention will be different from that of natural coral, and have novelty.

In conclusion, the invention provides the stable optimal growth environment and nutrition of the small-hydroid hard coral by monitoring the seawater environment in the water tank, so that the small-hydroid hard coral can be produced in mass; in addition, the coral culture method of the invention is realized by the coral culture system, so that the obtained coral product has stable and excellent quality.

Drawings

FIG. 1 is a schematic diagram of a coral culture system.

Fig. 2A and 2B are photographs of coral.

Fig. 3A to 3C are photographs of coral bone pieces.

FIG. 4 is a photograph of coral bone test pieces.

FIG. 5A is a photograph of coral bone powder; FIG. 5B is a photograph of coral bone particles at 500 Xmagnification; fig. 5C and 5D are 4000-fold magnified photographs of coral bone particles.

Detailed Description

Hereinafter, the advantages and effects achieved by the present invention will be easily understood by those skilled in the art from the following examples. Accordingly, it is to be understood that the description set forth herein is merely illustrative of the preferred embodiments and is not intended to limit the scope of the invention, as various modifications, alterations may be made in the practice or application of this invention without departing from the spirit or scope thereof.

Example 1: coral culture

Culturing coral in a closed culture manner and in circulating seawater in an indoor glass culture tank, namely, the glass culture tank is not communicated with an open sea area so as to directly introduce or discharge seawater; wherein the seawater is obtained from natural seawater, and after precipitation and purification, various parameters of the seawater are adjusted (as described later); wherein the coral comprises beautiful axial hole coral, noble axial hole coral, simple axial hole coral, kidney-shaped euglena (Fimbriaphyllia ancora), spike soft coral (Dendronepythya sp.) and gorgon fruit (Dendronepythya sp.), and is cultivated in grooves. Kidney-shaped euglena, glabrous sarcandra and gorgon fruit non-small hydroid hard coral are used for comparison. The coral used in the invention is obtained by artificial culture and is not wild coral.

Firstly, taking a point-shaped coral segment from an artificially cultured coral mother plant, wherein the point-shaped coral segment comprises calcium carbonate particles and coral worms, the particle size of the calcium carbonate particles is about 0.2 cm to 0.5 cm, and inoculating and fixing the point-shaped coral segment on a cylindrical ceramic substrate or a cement tray so as to facilitate the growth of the coral segment; wherein the density of the punctiform coral fragments is 50 to 60 per square meter, and the punctiform coral fragments only leave the sea water for a short time when being inoculated; wherein the coral worm comprises symbiotic algae.

After the coral segment inoculation is completed, the rotifer is provided as bait, and is fed for 1 to 3 times per week, the water quality and balance of the circulating seawater are continuously monitored at a frequency of 8 to 12 times per day, and an automatic replenishment and purification module is set to maintain the pH value of the circulating seawater at 7.8 to 8.8, the salinity at 29ppt to 37ppt, the alkalinity at 7dKH to 10dKH, the temperature at 20 ℃ to 26 ℃, the phosphate concentration at less than 0.03ppm, the nitrate concentration at less than 0.1ppm, the nitrite concentration at less than 0.1ppm, the calcium ion concentration at 430ppm to 500ppm, and the magnesium ion concentration at 1290ppm to 1500ppm.

The lower jar of glass jar of breeding is the aqua storage tank, except can store the clean sea water after filtering to set up the water purification module, this water purification module includes: biochemical cotton with the aperture of 0.1mm, biochemical cotton with the aperture of 0.3 mm, a ceramic ring with the aperture of 0.01 mm to 0.05 mm, filter cotton with the aperture of 0.1mm to 0.3 mm, coral filter stones and a movable Dan Shanhu reef are used for rapidly treating and controlling the quality of circulating seawater. In addition, the protein demister is used for removing floating foam on the surface layer of the circulating seawater so as to reduce organic matters such as protein, amino acid and the like generated by coral.

The light emitting diode is selected, comprising: 2800K to 3800K white light, 5000K to 6500K white light, 425nm to 435nm blue light and 445nm to 470nm blue light, and providing light for a total light time of 12 hours for symbiotic algae to photosynthesis at intervals of several times a day. Finally, the filtered water amount was 5.56 volume percent per minute based on the total volume of seawater in the glass jar (without lower jar and line).

Comparative experiment

The following describes the difference in parameter settings and the cultivation results for each cultivation condition, respectively, wherein:

O: indicating good coral growth.

X: indicating death or deterioration of the water quality of coral.

Delta: indicating poor coral growth or reduced growth rate.

Experiment 1: pH value of

The culture conditions of each group in this experiment were similar to those in example 1 above, except that the pH was different, and the results are shown in Table 1.

Table 1: cultivation results at different pH values

	7.7	7.8	8.3	8.8	8.9
						Beautiful coral with shaft hole	△	O	O	O	△
Noble coral with shaft hole	△	O	O	O	△
						Simple shaft hole coral	△	O	O	O	△
Kidney-shaped aucubia japonica	△	O	O	X	X

As can be seen from Table 1, when the pH was maintained at 7.8 to 8.8, the beautiful, noble and simple shaft hole corals were most favored for growth.

Experiment 2: salinity of

The culture conditions of each group in this experiment were similar to those in example 1 above, except that the salinity was different, and the results are shown in Table 2.

Table 2: cultivation results of different salinity

28ppt

29ppt

30ppt

34ppt

37ppt

38ppt

Beautiful coral with shaft hole

X

△

O

△

Noble coral with shaft hole

X

△

O

△

Simple shaft hole coral

X

△

O

△

Kidney-shaped aucubia japonica

△

O

△

As can be seen from Table 2, when the salinity is 29ppt to 38ppt, beautiful axial hole coral, noble axial hole coral and simple axial hole coral can grow slowly; when the salinity is 30ppt to 37ppt, the growth of beautiful shaft hole coral, noble shaft hole coral and simple shaft hole coral is most facilitated.

Experiment 3: alkalinity (basicity)

The culture conditions of each group in this experiment were similar to those in example 1 above, except that the alkalinity was different, and the results are shown in Table 3.

Table 3: cultivation results with different alkalinity

From Table 3, it can be seen that when the basicity is maintained at 7dKH to 10dKH, the beautiful axial hole coral, the noble axial hole coral and the simple axial hole coral are most favored to grow.

Experiment 4: temperature (temperature)

The cultivation conditions of each group in this experiment were similar to those in example 1 above, except that the temperature was different, and the results are shown in Table 4.

Table 4: cultivation results at different temperatures

	19℃	20℃	23℃	26℃	27℃
						Beautiful coral with shaft hole	△	O	O	O	X
Noble coral with shaft hole	△	O	O	O	X
						Simple shaft hole coral	△	O	O	O	X
Kidney-shaped aucubia japonica	O	O	O	X	X

As can be seen from Table 4, when the temperature was maintained at 20℃to 26℃it was most advantageous for the growth of beautiful axial hole coral, noble axial hole coral and simple axial hole coral.

Experiment 5: magnesium ion concentration

The cultivation conditions of each group in this experiment were similar to those in example 1 above, except that the magnesium ion concentration was different, and the results are shown in Table 5.

Table 5: cultivation results of different magnesium ion concentrations

	1050ppm	1290ppm	1395ppm	1500ppm	1700ppm
						Beautiful coral with shaft hole	△	O	O	O	X
Noble coral with shaft hole	△	O	O	O	X
						Simple shaft hole coral	△	O	O	O	X
Herba Pileae Scriptae	△	O	O	△	X

As can be seen from Table 5, when the concentration of magnesium ions was maintained at 1290ppm to 1500ppm, the beautiful axial hole coral, the noble axial hole coral and the simple axial hole coral were most favorable for growth. In addition, when the magnesium ion concentration is 1050ppm, the beautiful axial hole coral, the noble axial hole coral, and the simple axial hole coral may be discolored.

Experiment 6: concentration of calcium ion

The culture conditions of each group in this experiment were similar to those in example 1 above, except that the calcium ion concentration was different, and the results are shown in Table 6.

Table 6: cultivation results of different calcium ion concentrations

As can be seen from table 6, when the concentration of the calcium ions was maintained at 430ppm to 500ppm, it was most advantageous for the growth of beautiful axial hole coral, noble axial hole coral, and simple axial hole coral; wherein, when the calcium ion is 400ppm, the growth rate of beautiful axial hole coral, noble axial hole coral and simple axial hole coral is slowed down.

Experiment 7: filtered water volume

The cultivation conditions of each group in this experiment were similar to those in example 1 above, except that the filtration rate, that is, the amount of filtered water per minute was different, and the results are shown in Table 7.

Table 7: cultivation results of different filtered water volumes

	2.5％	3％	4％	5.56％
					Beautiful coral with shaft hole	X	△	O	O
Noble coral with shaft hole	X	△	O	O
					Simple shaft hole coral	X	△	O	O

Note that: % is the volume percent of filtered water per minute relative to the total volume of seawater in the glass jar (without lower jar and piping).

As can be seen from Table 7, when the amount of filtered water is 4 to 5.56 volume percent per minute, the beautiful axial hole coral, noble axial hole coral and simple axial hole coral are most favorable to grow.

Experiment 8: phosphate, nitrate and nitrite concentrations

The cultivation conditions of each group of experiments were similar to those of example 1 above, except that the concentrations of phosphate, nitrate and nitrite were different, and the results are shown in Table 8.

Table 8: cultivation results with different phosphate, nitrate and nitrite concentrations

As can be seen from Table 8, when the concentration of phosphate is less than 0.03ppm, the concentration of nitrate is less than 0.5ppm, and the concentration of nitrite is less than 0.1ppm, the growth of beautiful axial hole coral, noble axial hole coral, and simple axial hole coral is most favored.

Experiment 9: water purifying module

The culture conditions of each group of experiments are similar, the difference is only that the water purification modules are different, and the results are shown in Table 9; wherein, the water purifying module of the group A comprises biochemical cotton, ceramic rings, filter cotton, coral filter stones and a movable Dan Shanhu reef; the water purifying module of the group B comprises biochemical cotton, ceramic rings, filter cotton, shell sand and living stone coral reefs.

Table 9: cultivation results of different water purification modules

	Group A	Group B
			Beautiful coral with shaft hole	O	△
Noble coral with shaft hole	O	△
			Simple shaft hole coral	O	△

As can be seen from Table 9, group A has good filtration effect, so that beautiful axial hole coral, noble axial hole coral and simple axial hole coral have good growth conditions; the group B adopts shell sand to replace coral filter stones, and the filtering effect is relatively poor, so the coral growth speed is not ideal as that of the group A.

Experiment 10: bait material

The culture conditions of each group of experiments are similar, and the difference is only that the feeding baits are different, and the results are shown in Table 10; wherein, group C is fed with paramecium; group D fed small and ultra-small rotifers; group E was fed with Bdellovely rotifers (Bdelloid rotifers).

Table 10: cultivation results of different baits

As can be seen from Table 10, the beautiful axial hole corals of group C and group D grow well, and the coral worms are fat and the grown coral bones are stronger; in comparison, the beautiful axial hole coral and kidney-shaped euglena of group E are relatively poor in growth condition, wherein coral worms of the beautiful axial hole coral are tiny, and the produced coral bones are thin. It is known that feeding paramecium, small rotifer or microminiature rotifer contributes to the growth of beautiful coral shaft hole.

Example 2: coral culture System

As shown in fig. 1, the coral culture system 10 includes: a sea water 110; a water tank 120, wherein the water tank 120 is used for accommodating the seawater 110, and at least one base 130 is arranged on the bottom surface of the water tank, the at least one base 130 is used for accommodating a coral 20, and the filtered water amount is at least 2.6 volume percent per minute based on the total volume of the seawater 110 in the water tank 120; a light source module 140 for providing the coral 20 with light for at least 6 hours each day; a water purification module 150 for filtering the seawater 110; a defoaming module 160 for removing the floating foam of the seawater 110; a pure water supply module 170 for supplying pure water to the seawater 110 and having a water supply port 171; a water storage tank 180 provided with a water inlet 181 and a water outlet 182; wherein the water inlet 181 and the water outlet 182 are respectively connected to the water tank 120 and the water storage tank 180, and the water supply port 171 is connected to the pure water supply module 170 and the water storage tank 180.

The light source module 140 is disposed above the water level of the seawater 110.

Preferably, the water storage tank 180 is disposed below the bottom of the water tank 120.

Preferably, the pure water supply module 170 further has a pure water inlet control module 172 for opening or closing the water supply port 171, wherein the water supply port 171 is adjacent to the water outlet 182, the pure water module 150 is accommodated in the water storage tank 180, and the pure water module 150 is adjacent to the water inlet 181.

The seawater is flowed by a pump motor (not shown).

Example 3: coral (coral)

As shown in fig. 2A, the exoskeleton of hard coral and coral worm are visible on coral branches; as shown in fig. 2B, coral 20 has a body 21 and a shoot 22.

Example 4: coral products

The coral product of this experiment may be coral bone that has not been chemically modified, and may be coral bone block (coral block). As shown in fig. 3A, the coral bone pieces were square, and each of the length, width, and height was 1.3 cm. As shown in fig. 3B, the coral bone pieces were rectangular parallelepiped in length of 2.5 cm, width of 1.2 cm, and height of 1 cm. As shown in FIG. 3C, the coral bone pieces were cylindrical in shape, approximately 3 cm in height and 2 cm in diameter.

Example 5: metal examination of coral products

The coral product of this experiment was a coral bone that was not chemically modified, sent to taiwan test technologies, inc., and analyzed by inductively coupled plasma atomic emission spectrometry (ICP-OES) according to the general rule of the modified heavy metal test method issued by taiwan health welfare agency, food word 1031901169, and the results are shown in Table 11.

Table 11: metal examination results of coral products

Detecting items	Test results	Limit of quantification/detection	Unit (B)
				Arsenic (As)	Not detected	2.0	ppm(mg/kg)
Lead (Pb)	Not detected	2.0	ppm(mg/kg)
				Cadmium (Cd)	Not detected	2.0	ppm(mg/kg)
Mercury (Hg)	Not detected	2.0	ppm(mg/kg)
				Copper (Cu)	Not detected	2.0	ppm(mg/kg)
Calcium (Ca)	297170.8	2.0	ppm(mg/kg)
				Phosphorus (P)	20.9	2.0	ppm(mg/kg)
Magnesium (Mg)	982.6	2.0	ppm(mg/kg)
				Potassium (K)	83.2	2.0	ppm(mg/kg)
Zinc (Zn)	Not detected	2.0	ppm(mg/kg)
				Iron (Fe)	9.6	2.0	ppm(mg/kg)
Manganese (Mn)	Not detected	2.0	ppm(mg/kg)
				Selenium (Se)	Not detected	2.0	ppm(mg/kg)
Sodium (Na)	3547.4	2.0	ppm(mg/kg)

As can be seen from Table 11, the tested items of the coral product of the present invention contained arsenic, lead, cadmium, mercury, copper, calcium, phosphorus, magnesium, potassium, zinc, iron, manganese, selenium, and sodium, and based on the total weight of the results obtained in the tested items, the content of calcium was 98.46141 wt%, the content of phosphorus was 0.006925 wt%, the content of magnesium was 0.325564 wt%, the content of potassium was 0.027567 wt%, the content of iron was 0.003181 wt%, and the content of sodium was 1.175358 wt%, wherein the content of arsenic, lead, cadmium, mercury, and copper, which were significantly toxic to living things, were not detected, indicating that the coral product of the present invention was safe for human body. Finally, selenium was also undetected.

Example 6: component analysis of coral products

The coral product of this experiment was a coral bone that was not chemically modified, sent to ultra-micro industrial safety laboratory TEST by taiwan TEST technologies, inc., and analyzed by inductively coupled plasma atomic emission spectrometry (ICP-OES) according to the certified self-established method (TEST-UG-0435), and the results are shown in Table 12.

Table 12: component analysis results of coral product

Detecting items	CAS NO.	Test results	Limit of quantification/detection	Unit (B)
					Arsenic (As)	7440-38-2	Not detected	2.0	ppm(mg/kg)
Lead (Pb)	7439-92-1	Not detected	2.0	ppm(mg/kg)
					Mercury (Hg)	7439-97-6	Not detected	2.0	ppm(mg/kg)
Cadmium (Cd)	7440-43-9	Not detected	2.0	ppm(mg/kg)
					Magnesium (Mg)	7439-95-4	807	2.0	ppm(mg/kg)
Phosphorus (P)	7723-14-0	28.8	10.0	ppm(mg/kg)
					Manganese (Mn)	7439-96-5	Not detected	2.0	ppm(mg/kg)
Zinc (Zn)	7440-66-6	Not detected	2.0	ppm(mg/kg)
					Copper (Cu)	7440-50-8	Not detected	2.0	ppm(mg/kg)
Iron (Fe)	7439-89-6	368	2.0	ppm(mg/kg)
					Potassium (K)	7440-09-7	78.1	2.0	ppm(mg/kg)
Sodium (Na)	7440-23-5	4110	2.0	ppm(mg/kg)
					Calcium (Ca)	7440-70-2	377000	100	ppm(mg/kg)
Selenium (Se)	7782-49-2	Not detected	2.0	ppm(mg/kg)
					Silicon (Si)	7440-21-3	367	10.0	ppm(mg/kg)

As can be seen from Table 12, the analysis items of the coral product of the present invention were newly added with silicon in comparison with example 5, and based on the total weight of the results obtained in the analysis items, the content of calcium was 98.49542 wt%, the content of phosphorus was 0.007524 wt%, the content of magnesium was 0.210838 wt%, the content of potassium was 0.020404 wt%, the content of iron was 0.096144 wt%, the content of sodium was 1.073783 wt%, and the content of silicon was 0.095883 wt%, wherein the content of arsenic, lead, cadmium, mercury and copper, which were remarkably toxic to living things, were not detected, indicating that the coral product of the present invention can be safely used in human body. Finally, selenium was also undetected.

Furthermore, as can be seen from a comparison of examples 5 and 6, although the test methods are not necessarily the same, the coral product of the present invention contains the first three elements of calcium, sodium, and magnesium in sequence, and the total weight of calcium, sodium, and magnesium is greater than 99.5 weight percent; wherein calcium accounts for 98.46141 weight percent and 98.49542 weight percent respectively, and is the main component. It is known that the coral product of the present invention is rich in calcium, namely calcium carbonate, and can be used as a raw material for artificial replacement of bones, thereby having market potential.

Example 7: compression strength test

The coral product in this experiment was a coral bone that had not been chemically modified, and the average diameter was 10.1 millimeters (mm) and the average height was 15.1 millimeters, as shown in FIG. 4, using this as a test piece. The test is performed with reference to the specifications of ISO 13175-3 (2012); wherein the test piece is adjusted to 23+ -2deg.C, the relative humidity is 50+ -10%, and the time is more than 24 hours. Laboratory conditions were 23.+ -. 2 ℃ and relative humidity was 50.+ -. 10%. The test speed was 0.50 millimeters per minute (mm/min); the material tester was a MTS Criterion C43 Universal tester (Universal TESTING MACHINE) with a steel ball diameter of 12.7 mm. The test pieces were 10 in total, and the results are shown in Table 13.

Table 13: maximum compressive load (unit: kilogram force (kgf))

Numbering device	Maximum compressive load (kgf)
		#1	121
#2	122
		#3	211
#4	78.7
		#5	120
#6	82.0
		#7	70.6
#8	98.4
		#9	74.8
#10	36.6
		Average of	102
Standard deviation of	47

As can be seen from Table 13, the maximum compressive load of the present invention is 36.6 Kg to 211 Kg, the average maximum compressive load is 102 Kg, and the present invention has excellent maximum compressive load, i.e., excellent compressive strength, and is suitable for use as a raw material for artificial replacement bone.

Example 8: analysis of diameter of through holes

The coral article of this experiment was a coral bone that was not chemically modified, and the test specimen was in the form of a granular form and a white powder with an average particle diameter of about 250 microns, as shown in FIG. 5A. The test was performed with reference to the specification of ISO 13175-3 (2012), and through-hole observation was performed using a scanning electron microscope and the diameter thereof was measured (brand: topcon; model: SM-300), wherein a 500-fold enlarged view of a single powder is shown in fig. 5B, the circled position was enlarged to 4000 times, and the Z-axis of the photographing angle was 0 degrees, as shown in fig. 5C, and 10 through-holes were arbitrarily selected to measure the diameter, as shown in fig. 5D, and the results are shown in table 14.

Table 14: diameter of through hole (unit: micrometers (μm))

Numbering device	Diameter of through hole (mum)
		#1	1.245
#2	0.805
		#3	0.815
#4	1.114
		#5	1.401
#6	0.761
		#7	0.805
#8	0.660
		#9	0.510
#10	1.637
		Average of	0.975
Standard deviation of	0.359

As can be seen from Table 14, even after the coral article of the present invention was ground into fine powder, it was observed that calcium carbonate secreted by coral worms was connected to each other and stacked in a granular form in the 4000-fold enlarged view of FIG. 5C, and formed through-holes 23A, 23B as shown in FIG. 5C, and had diameters of 0.510 μm to 1.637 μm and average through-hole diameters of 0.975. Mu.m. The coral bone of the present invention has complicated inner connecting channel owing to the observed through holes on the surface of the polished grains. Therefore, when the coral bone is used for a human body, the internal connecting channels are beneficial to the circulation of active substances and nutrients, and are beneficial to the bone repair.

Example 9: through-hole uniformity deviation

Following example 7, the center-to-center spacing of two of the 10 vias was further measured at the same 4000-fold magnification, and the results are shown in table 15.

Table 15: center-to-center spacing (Unit: micrometers (μm))

As shown in Table 15, the average value of the center-to-center distances of the two through holes of the coral bone which is not chemically modified in the invention is 7.228 microns, and the standard deviation is only 1.331 microns, which shows that the dispersion degree of the center-to-center distances of the two through holes of the coral bone which is not chemically modified in the invention is low, that is, the through holes of the coral bone which is not chemically modified in the invention are uniformly distributed, and the research is carried out because the coral culture method of the invention provides a stable growing environment for the small-hydroid hard coral, so that the coral bone can stably grow to form uniformly distributed holes.

Example 10: qualitative characterization of crystalline phases

The coral product of this experiment was a coral bone that was not chemically modified, and the test sample was also a powder as in example 7, and was subjected to crystalline phase characterization as specified in ISO 13175-3 (2012), using a multi-functional micro-area X-ray Diffraction (XRD) (brand: bruker; model: D8 Discover), with a scan angle ranging from 20 ^○ to 80 ^○ in terms of 2θ.

The Crystallinity (CRYSTALLINITY) of 79.9% and the amorphism (Amorphous) of 20.1% were measured qualitatively in crystalline phase, which shows that the chemically unmodified coral bone of the present invention has a high proportion of crystals, i.e., high regularly arranged areas, which contributes to improved mechanical strength.

In summary, the cultivation method of the invention can effectively produce the hard coral with small hydroids in a large quantity, belongs to an indoor cultivation method, eliminates the doubt that the hard coral with small hydroids is polluted by sea, and the obtained coral bone component which is not subjected to chemical modification has no heavy metal, excellent maximum compressive load, complex internal connecting pipe and low hole uniformity deviation, is beneficial to commodity standardization, can be applied to the medical field with high standard, and has high market potential.

The examples are given for convenience of illustration only, and the embodiments are not intended to limit the scope of the invention as claimed; other changes, modifications, etc. which do not depart from the spirit of the invention are intended to be included within the scope of the invention as defined by the appended claims.

Claims

1. A coral article comprising a calcium component and a magnesium component and having a plurality of through-holes; wherein the calcium component comprises calcium and the magnesium component comprises magnesium, and the content of calcium is greater than or equal to 95 weight percent, the content of magnesium is less than or equal to 1 weight percent, and the metal element comprises calcium, magnesium, potassium, iron and sodium, and the non-metal element comprises phosphorus, based on the total weight of the metal element and the non-metal element contained in the coral article; the coral product is obtained by processing from hydra minor hard coral; wherein the coral product has an average maximum compressive load of 50 kg force to 200 kg force; the coral article has a through-hole average diameter of 0.5 microns to 1.7 microns; the average distance between the centers of two through holes of the coral product is 5 micrometers to 10 micrometers; and the coral article has a crystallinity of 79% to 81%, and an amorphism of 19% to 21%.

2. The coral article of claim 1, wherein the coral article is a geometric body and has a length, width, and height of 0.2 cm to 12 cm.

3. A coral article as defined in claim 2, wherein the geometry is square and has a length, width, and height of 0.2 cm to 3.5 cm.

4. The coral article of claim 2, wherein the geometric body is a cuboid and has a length of 0.3 cm to 5 cm; a width of 0.2 cm to 3.5 cm; and a height of 0.2 cm to 3.5 cm.

5. The coral article of claim 2, wherein the geometric body is a cylinder and has a diameter of 0.2 cm to 3.5 cm and a height of 0.5 cm to 7 cm.

6. A coral article as defined in claim 1, wherein the standard deviation of the spacing between the centers of the two through holes of the coral article is less than 1-2 of the average spacing between the centers of the two through holes.

7. A coral product as defined in claim 1, wherein the hard coral is selected from the group consisting of: beautiful axial hole coral, noble axial hole coral, simple axial hole coral, gorgeous axial hole coral, branch axial hole coral, small She Zhoukong coral, middle axial hole coral and Buddha axial hole coral.