WO2013095021A1

WO2013095021A1 - Integrated multi-trophic aquaculture system with tourism purpose

Info

Publication number: WO2013095021A1
Application number: PCT/KR2012/011211
Authority: WO
Inventors: Seong Jae Jeong; Mi Seon Park; Heui Chun An; Young Dae Kim; Tae Seok Moon; Byung Hwa Min; Jae Man Kim; Jung Kil Ahn
Original assignee: National Fisheries Research And Development Institute; Md Co., Ltd.
Priority date: 2011-12-21
Filing date: 2012-12-20
Publication date: 2013-06-27
Also published as: KR101174864B1

Abstract

Provided is an integrated multi-trophic aquaculture system with tourism purpose. The system is configured such that: a foothold and a safety rail are installed on an upper surface of a mooring unit of the system to provide a breeding passage for culture management and a watching passage for visitors; an invertebrate farming cage is mounted to a lower side of a fish farming cage; a lower end net in a sunshade shape, being hung on a seabed, is installed at a lower side of the invertebrate farming cage; and a natural fish reef or an artificial fish reef is disposed inside the lower end net, so that various kinds of aquatic organisms can be simultaneously cultivated in one aquafarming cage, feed residues or excrements generated from the fish farming cage can become foods and nutrients for shellfishes, sea cucumbers, and abalones growing in the lower side of the fish farming cage.

Description

INTEGRATED MULTI-TROPHIC AQUACULTURE SYSTEM WITH TOURISM PURPOSE

The present invention relates to an integrated multi-trophic aquaculture (IMTA) system with tourism purpose, which is configured such that: a foothold and a safety rail are installed in a mooring unit of an aquafarming cage; the aquafarming cage is divided into a fish farming cage and an invertebrate farming cage of a lower side of the fish farming cage; and a lower end net in a sunshade shape is mounted to a lower side of the invertebrate farming cage so as to provide a growth space for sea cucumbers, abalones or the like on a seabed, so that the aquaculture system is very economical, eco-friendly and can provide excellent productivity and various spectacles.

In general, an aquaculture system using an aquafarming cage means a facility in which the aquafarming cage is installed up to a predetermined scope in coastal waters or the open sea to cultivate various fishes at high density in an inner part thereof. As water quality in coastal waters has been polluted, the aquaculture system using the aquafarming cage is on a transferring trend onto the open water in which the depth of water is deep relatively. The scale thereof also becomes larger gradually.

In the aquaculture system using the aquafarming cage as described above, seawater in the inside and outside of the aquafarming cage freely passes through the net meshes of the aquafarming cage, thereby enabling the exchange of seawater and the supply of oxygen to be smoothly performed. Of course, since excrements or feed residues generated during the metabolic process of cultivated fishes are automatically discharged into the lower side of the aquafarming cage, it is not necessary to separately perform a work for removing wastes. Furthermore, even if a great amount of fishes are cultivated at high density, water quality in the aquafarming cage is not deteriorated. Thus, in view of sea farming on a large scale, the aquaculture system can provide various advantages.

However, in spite of various advantages, since the conventional aquaculture system using the aquafarming cage is configured to cultivate only specific fishes within the aquafarming cage, it is problematic that an aspect of productivity to simultaneously cultivate various aquatic organisms in one aquafarming cage and an aspect to utilize the aquaculture system using the aquafarming cage as the tour package of a sea village by providing useful spectacles based on the diversity of aquatic organisms are hardly considered.

Furthermore, although the excrements or feed residues of fishes discharged through a bottom part of the aquafarming cage may be provided as good foods and nutrients for stereotactic (i.e. a property to be attached to a seabed or a rock) organisms such as sea cucumbers or abalones as well as various shellfishes which grow in the seabed, they are not systematically and efficiently utilized, but are unnecessarily discharged into the sea. Thus, it is problematic that they fell so low as to become a factor to contaminate the water quality of coastal waters.

In addition to this, since the conventional aquaculture system using the aquafarming cage is configured such that a ship directly comes alongside the mooring unit located in the upper part of the aquafarming cage, in a case where a strong impact occurs when the ship comes alongside the mooring unit, riskiness of a breakdown of the mooring unit itself becomes high. Furthermore, it is problematic since the impact, vibration and noise acting on the mooring unit are directly transmitted to the aquafarming cage, many stresses are applied to fishes, and thus they also have a bad effect on the growing conditions of fishes.

Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art. A first aspect of the present invention is intended to provide an integrated multi-trophic aquaculture system with tourism purpose, which is configured such that: a foothold and a safety rail are installed on an upper surface of a mooring unit of the system to provide a breeding passage for culture management and a watching passage for visitors; an invertebrate farming cage is mounted to a lower side of a fish farming cage; a lower end net in a sunshade shape, being hung on a seabed, is installed at a lower side of the invertebrate farming cage; and a natural fish reef or an artificial fish reef is disposed inside the lower end net, so that various kinds of aquatic organisms can be simultaneously cultivated in one aquafarming cage, feed residues or excrements generated from the fish farming cage can become foods and nutrients for shellfishes, sea cucumbers, and abalones growing in the lower side of the fish farming cage, thereby enabling very economical, eco-friendly and excellent productivity and various spectacles to be provided.

In addition to this, a second aspect of the present invention serves to provide an integrated multi-trophic aquaculture system with tourism purpose, which is configured such that: a mooring unit is produced using buoyant tubes made of a polyethylene material, and tube holders in which a foothold and a safety rail are assembled, whereby the mooring unit having very excellent corrosion resistance, wave resistance, and mechanical strength can be provided; buoyant tubes for bumper function are additionally disposed outside the mooring unit at predetermined intervals, whereby the buoyant tubes for bumper function can absorb an impact generated when a ship comes alongside the mooring unit, thereby minimizing both a breakage of the mooring unit itself due to the impact and stresses applied to cultivated fishes.

Furthermore, a third aspect of the present invention serves to provide an integrated multi-trophic aquaculture system with tourism purpose, which is configured such that hanging aquaculture ropes are mounted to the tube holders for bumper function for installation of the buoyant tubes for bumper function so that various seaweeds for providing a spawning ground and a feeder of various fishes can cling to and grow around the mooring unit, and various fishes as well as cultivated fishes based on these seaweeds and feed ingredients for cultivated fishes can gather around the aquaculture system, thereby enabling the aquaculture system to be utilized as more excellent tour package.

Furthermore, a fourth aspect of the present invention serves to provide an integrated multi-trophic aquaculture system with tourism purpose, which is configured such that a cage frame having a predetermined level of buoyancy is connected to the outside of the aquafarming cage at a location corresponding to a boundary surface between the fish farming cage and the invertebrate farming cage, and the cage frame is connected to an anchor means by anchoring ropes so that the aquafarming cage floats on water due to the cage frame, thereby enabling transportation or movement, and installation or removal works of the aquaculture system to be easily performed on water, and at the same time as this, unnecessary ropes can be easily managed not to be exposed around the mooring unit, thereby enabling a ship to safely come alongside the mooring unit and contributing to the improvement of a view of surrounding.

In an aspect, the present invention provides an integrated multi-trophic aquaculture system with tourism purpose, the aquaculture system including: an aquafarming cage for providing a net space in which aquatic organisms are cultivated; a mooring unit which is installed to float on the surface of water in a state of the aquafarming cage being connected to a lower side thereof; an anchor means for fixing both the aquafarming cage and the mooring unit to a seabed using anchoring ropes, wherein a foothold and a safety rail for providing a breeding passage and a watching passage are installed on an upper surface of the mooring unit, wherein the aquafarming cage includes a fish farming cage for providing a net space in which fishes are cultivated, and an invertebrate farming cage which is formed as a separate net space at a lower part of the fish farming cage, wherein an openable zipper door is installed at a body net or a bottom net of each of the fish farming cage and the invertebrate farming cage, and wherein a lower end net, which is connected to the peripheral edge of the bottom net in a sunshade shape and is in close contact with a seabed, is mounted to a lower part of the invertebrate farming cage.

Furthermore, the aquaculture system according to present invention is characterized in that: an artificial fish reef may be disposed in a space inside the lower end net; the mooring unit may include: tube holders which are radially disposed along a peripheral edge of an upper end of the aquafarming cage at regular intervals, and buoyant tubes which are connected to the outside of the aquafarming cage in a concentric circle shape, wherein each of the tube holders may be configured such that a plurality of tube rings for the connecting of the buoyant tubes are integrally formed with a lower side of a support frame, and an assembly end for assembling both the foothold and the safety rail may protrude from an upper side of the support frame.

In addition to this, the aquaculture system according to present invention is characterized in that: tube holders for bumper function which radially protrude at regular intervals, and buoyant tubes for bumper function which are installed in a circular shape along the tube rings of the outside of the tube holders for bumper function may be additionally installed at an outer peripheral edge of the mooring unit; hanging aquaculture ropes being hung in water are mounted to the tube holders for bumper function; the cage frame having the predetermined level of buoyancy is connected to the outer peripheral edge of the aquafarming cage at a location corresponding to the boundary surface between the fish farming cage and the invertebrate farming cage; and the anchor means is connected to the cage frame using the anchoring ropes.

As described above, the aquaculture system according to the present invention has an effect that various kinds of aquatic organisms can be simultaneously cultivated in one aquafarming cage, feed residues or excrements generated from the fish culture space can be used as foods and nutrients for shellfishes, sea cucumbers, or abalones growing in the lower side of the aquafarming cage, thereby enabling very economical, eco-friendly and excellent productivity to be provided.

Furthermore, the aquaculture system according to the present invention is advantageous that the mooring unit is produced based on the buoyant tubes made of polyethylene, and the tube holders in which the foothold and the safety rail are assembled, and which are made of the same material as the buoyant tubes, and buoyant tubes for bumper function are additionally disposed outside the mooring unit at regular intervals, whereby the buoyant tubes for bumper function can absorb an impact generated when a ship comes alongside the mooring unit, thereby minimizing both a breakage of the mooring unit due to the impact and stresses applied to cultivated fishes.

Also, it is advantageous because various seaweeds for providing the spawning ground and feeder of various fishes cling to and grow in the hanging aquaculture ropes around the mooring unit, various fishes as well as cultivated fishes based on these seaweeds and feed ingredients for cultivated fishes can gather around the aquaculture system, thereby enabling the aquaculture system to be utilized as more excellent tour package.

In addition, it is advantageous that transportation or movement, and installation or removal works of the cultivating system can be easily performed by floating the aquafarming cage using the cage frame collaterally used as a buoyant element, and that unnecessary ropes are managed not to be exposed around the mooring unit, thereby enabling a ship to safely come alongside the mooring unit and contributing to the improvement of a view of surrounding.

FIG. 1 is a side view showing an installation state of an integrated multi-trophic aquaculture system with tourism purpose according to the present invention;

FIG. 2 is an exploded perspective view showing an aquafarming cage used in the present invention;

FIG. 3 is a side view showing an enlarged subject matter of a mooring unit used in the present invention;

FIG. 4 is a plane view of FIG. 3;

FIG. 5 is a plane view showing a state in which a foothold and a safety rail are removed from FIG. 4; and

FIG. 6 is a plane view showing an aquafarming cage frame used in the present invention.

Hereinbelow, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As illustrated in FIG. 1, an integrated multi-trophic aquaculture system with tourism purpose according to the present invention includes: an aquafarming cage 2 for providing a net space in which aquatic organisms are cultivated; a mooring unit 1 installed to float on the surface of water in a state of the aquafarming cage 2 being connected to a lower side thereof; and an anchor means, namely, an anchor 9a and a concrete block 7 in the drawings, for fixing both the aquafarming cage 2 and the mooring unit 1 to a seabed using anchoring ropes 9. This is typically applied to an aquaculture system using an aquafarming cage.

The constituent element corresponding to a first subject matter of the present invention is a structural improvement matter of the aquafarming cage 2, as illustrated in FIG. 1 and FIG. 2. It is that a fish farming cage 3 for providing a net space in which fishes are cultivated, and an invertebrate farming cage 4 for providing a separate net space in a lower part of the fish farming cage 3 are divided and formed into up and down inside one aquafarming cage 2.

The fish farming cage 3 and the invertebrate farming cage 4 comprise

body nets

3a, 4a and

bottom nets

3b, 4b, respectively. In this state, an upper end part of the body net 4a of the invertebrate farming cage 4 is connected to an edge of the bottom net 3b of the fish farming cage 3, a cover net 2a is located at an upper side of the fish farming cage 3, and a lower end net 5, which is connected to along a peripheral edge of the bottom net 4b in a sunshade shape and is in close contact with a seabed, is mounted to a lower part of the invertebrate farming cage 4.

Openable zipper doors

3c, 4c for the charge or discharge of aquatic organisms or the entry of divers are installed at the

bottom nets

3b, 4b of the fish farming cage 3 and the invertebrate farming cage 4. Furthermore, due to the lower end net 5, spontaneous fish reefs, for example, rocks, are located in a space provided between the invertebrate farming cage 4 and the seabed, or small-sized artificial fish reefs 5b are placed therein, so that a bottom construction where stereotactic organisms such as sea cucumbers or abalones attach and inhabit can be provided.

The

openable zipper doors

3c, 4c may be installed at the

body nets

3a, 4a or may be formed as a U-shaped door as well as a door in the shape of "ㅡ" or "ㅣ". If those allow the charge or discharge of the aquatic organisms or the entry of divers, doors in various types such as a window type door and the like in addition to the zipper type door may be used. The invertebrate farming cage 4 may be also divided into two or more net spaces as needed.

Meanwhile, sinkers 5a are mounted to the lower end part of the lower end net 5 at regular intervals so that the lower end net 5 can be in close contact with the seabed. The reason of installation of the sinkers 5a is to enable the young seeds or shells of aquatic organisms to enter into the inside of the lower end net 5 along the seabed, and the aquatic organisms not to easily escape to the outside after they grow in the inside of the lower end net 5 during a predetermined period of time.

As needed, a sinking reinforcement rim may be mounted to the lower end part of the lower end net 5. The artificial fish reefs 5b disposed inside the lower end net 5 may also use fish reefs having an appropriate shape according to the kind of organisms to be cultivated. However, a method of reducing typical artificial fish reefs produced only for sea cucumbers or abalones to an appropriate size and piling up them in a rock form is the most appropriate for the fish reefs.

The size of meshes applied to the fish farming cage 3, the invertebrate farming cage 4 and the lower end net 5 may be appropriately determined according to the kind of fishes or invertebrates to be cultivated in the aquafarming cage 2. In the case of the fish farming cage 3 and the invertebrate farming cage 4, the net is principally designed in a double net which comprises an external net that bears load, and an internal net for cultivating.

Also, as the external net is configured so that a length of each side which forms a mesh becomes at least more than 1.5 m, the entry of divers can be performed using the

zipper doors

3c, 4c installed in the internal net. Furthermore, the cover net 2a is installed at the mooring unit 2 to prevent cultivated fishes from escaping in the case of emergency, and usually puts in a state of being turned up to feed and observe the fishes.

By improving the structure of the aquafarming cage 2 by the above method, various aquatic organisms including fishes, shell shellfishes, sea cucumbers, abalones and the like can be simultaneously cultivated using one aquafarming cage 2.

Furthermore, feed residues or excrements generated from the fish farming cage 3 can be used as foods or nutrients for shell shellfishes, sea cucumbers and abalones which grow in a lower side of the fish farming cage 3. Accordingly, the present invention can provide an improved aquaculture system 10 having very economical, eco-friendly and excellent productivity.

The constituent elements corresponding to a second subject matter of the present invention are, as illustrated in FIG. 3 through FIG. 5, that the mooring unit 1 includes: tube holders 11 which are radially disposed along a peripheral edge of an upper end of the aquafarming cage 2 at regular intervals; and buoyant tubes 12 which are connected to an outside of the aquafarming cage 2 in a concentric circle shape using the tube holders 11, wherein a foothold 13 and a safety rail 14 for providing a breeding passage and a watching passage are installed on the upper surfaces of the tube holders 11.

Each of the tube holders 11 comprises: a grid support frame 11b; a plurality of tube rings 11a which are formed integrally with a lower side of the support frame 11b and provide a connection means for the buoyant tubes 12; and an assembly end 11c which protrudes from an upper end surface of the support frame 11b and providing a connection means of both the foothold 13 and the safety rail 14. The tube holders 11 are typically known components which have been widely used as various mooring constructions.

The tube holders 11, the buoyant tubes 12, the foothold 13 and the safety rail 14 have very excellent corrosion resistance mechanical strength, and reusability. Further, in view of securing structural strength and wave resistance of the mooring unit 1, it would be preferable that they are produced of meddle density polyethylene (MDPE) or high density polyethylene (HDPE) which enables them to be easily and firmly bonded and assembled by a thermal fusion method. A conventional method of mixing a steel material with foamed polystyrene (styrofoam) may be also applied thereto.

Each of the buoyant tubes 12 is produced in an arch shape corresponding to the intervals of the tube holders 11, and the buoyant tubes 12 are connected to each other to form a circular construction, and a barrier partition for water cut-off is formed in a connecting junction of the buoyant tubes 12. Thus, although a part of the buoyant tubes 12 which form the circular construction is damaged, seawater flows only into the damaged part of the buoyant tubes, but does not flow into the remaining parts of buoyant tubes 12, thereby enabling buoyancy of the mooring unit 1 to be stably maintained.

Also, the safety rail 14 is installed at both sides of the foothold 13 corresponding to an inner circumferential surface and an outer circumferential surface of the mooring unit 1 by combining a rail post 15 with a hand rail 15 so that the safety of administrators or visitors of the aquaculture system 10 can be sufficiently secured. Further, it would be preferable that a non-slip pad is attached to a surface of the foothold 13 or the surface of the foothold 13 is formed as a non-slip surface in an uneven shape.

In addition to this, as more clearly illustrated in FIG. 4 and FIG. 5, it would be most preferable that tube holders 11 for bumper function radially protrude at regular intervals in a state in which the tube holders 11 for bumper function are connected both to the buoyant tubes 12 and to the tube holders 11 for both the foothold 13 and the safety rail 14, and buoyant tubes 12 for bumper function be connected along the tube rings 11a of the outside of the tube holders 11 for bumper function so as to form a circular shape.

The number of the tube holders 11 for bumper function in the drawings is 1/2 of the number of tube holders 11 for both the foothold 13 and the safety rail 14. Each of the tube holders 11 for bumper function is installed to share one buoyant tube 12 that is located at the outside of the buoyant tubes 12 for supporting both the foothold 13 and the safety rail 14. The buoyant tubes 12 are configured such that a total of three lines for supporting the foothold 13 and the safety rail 14, and one line installed at the outside for bumper function are disposed in a concentric circle shape.

However, an application number and disposition state of the tube holders 11 for the foothold 13 and the safety rail 14, and the tube holders 11 for bumper function, and an arrangement state of the buoyant tubes 12 based on this are not limited to the shapes illustrated in FIG. 4 and FIG. 5. They may be freely determined according to the buoyancy or structural strength required for the mooring unit 1.

By installing the mooring unit 1 using the method as described above, the mooring unit 1 having very excellent wave resistance and structural strength can be provided. Furthermore, the buoyant tubes 12 for bumper function may absorb an impact generated when a ship comes alongside the mooring unit, thereby minimizing both a breakage of the mooring unit 1 and stresses applied to cultivated fishes.

The constituent elements correspond to a third subject matter of the present invention are, as illustrated in FIG. 1, that hanging aquaculture ropes 8 being hung in water are installed at the tube holders 11 for bumper function so that various seaweeds for providing a spawning ground and a feeder of various kinds of fishes can cling to and grow in the ropes 8 around the mooring unit 1, so that various fishes as well as cultivated fishes based on these seaweeds and feed ingredients for cultivated fishes can gather around the aquaculture system 10, thereby enabling the aquaculture system to be utilized as more excellent tour package.

Eight hanging aquaculture ropes 8 are preferably installed at regular intervals along the peripheral edge of the mooring unit 1. A separate PE pipe or a steel pipe may be used as facility for taking down and fixing the cultivating ropes 8. It would be preferable that the diameter of the aquaculture ropes 8 is about 20 mm, the intervals between the aquaculture ropes 8 are about 1 m, and the number of lines for taking down the ropes 8 is at least more than two. Furthermore, for the aquaculture ropes 8, standard thread ropes in which the germination spores of seaweeds are impregnated and cultivated may be used.

The constituent elements correspond to a fourth subject matter of the present invention are, as illustrated in FIG. 1, that the cage frame 6 having a predetermined level of buoyancy is connected to the outer peripheral edge of the aquafarming cage 2 at a location corresponding to the boundary surface between the fish farming cage 3 and the invertebrate farming cage 4, and that concrete blocks 7 and anchors 9a as the anchor means are connected to the cage frame 6 by anchoring ropes 9.

The cage frame 6 may use all materials if the materials can sufficiently endure various kinds of fluid resistances according to moorage of the aquaculture system 10, and a tensile force of the anchoring ropes 9 due to the buoyancy of the mooring unit 1, and can enable the aquafarming cage 2 and the lower end net 5 to float on the water surface by providing a larger buoyancy than a sinking force of the sinkers 5a installed at the lower end net, provided that the anchor means is not installed.

As a preferred embodiment of the cage frame 6, as illustrated in FIG. 6, the cage frame 6 can be collaterally used as a buoyant element by forming the cage frame 6 as an assembly of eight zinc plated steel pipes 17 having a diameter of about 250 mm and a thickness of about 5 mm. For this, assembly flanges 17a are formed in opposite ends of each steel pipe 17.

Also, it would be preferable that when the aquafarming cage 2 uses the double net comprising the external net and the internal net, the cage frame 6 is connected to the external net, and a holding ring (not drawn) for connection to the aquafarming cage 2 is formed on an inner circumferential surface of the cage frame 6. Furthermore, it would be preferable that a mooring pipe unit which was filed by the present applicant and registered under Korean Patent No. 10-0935238 is applied to a part in which the anchoring ropes 9 are connected to the cage frame 6.

When the cage frame 6 is installed using the method as described above, the aquafarming cage 2 floats on water using the buoyant element combined cage frame 6 so that towing type transportation or movement, and installation or removal works of the aquaculture system 10 using a ship can be more easily performed in water, and unnecessary ropes are managed not to be exposed around the mooring unit 1, thereby enabling a ship to safely come alongside the mooring unit and contributing to the improvement of a view of surrounding.

The present invention relates to an integrated multi-trophic aquaculture system, so the present invention has industrial applicability.

Claims

An integrated multi-trophic aquaculture system with tourism purpose, the aquaculture system (10) comprising:

an aquafarming cage (2) providing a net space for cultivating aquatic organisms;

a mooring unit (1) installed to float on water in a state of being connected to a lower side of the aquafarming cage (2); and

an anchor means for fixing the aquafarming cage (2) and the mooring unit (1) to a seabed using an anchoring rope (9),

wherein a foothold (13) and a safety rail (14) are installed on an upper surface of the mooring unit (1),

the aquafarming cage (2) comprises a fish farming cage (3) providing a net space for cultivating fishes and an invertebrate farming cage (4) formed at a lower part of the fish farming cage (3) to be form a separate net space,

openable zipper doors (3c), (4c) are installed in body nets (3a) (4a) or bottom nets (3b) (4b) of the fish farming cage (3) and the invertebrate farming cage (4),

a lower end net (5), which is connected to along a peripheral edge of the bottom net (4b) of the invertebrate farming cage (4) in a sunshade shape and is in close contact with the seabed, is installed at a lower part of the invertebrate farming cage (4),

a cage frame (6) having a predetermined level of buoyancy is connected to an outer peripheral edge of the aquafarming cage (2) at a location corresponding to a boundary surface of the fish farming cage (3) and the invertebrate farming cage (4), and

the anchor means is connected to the cage frame (6) by an anchoring rope (9).
The aquaculture system according to claim 1, wherein an artificial fish reef (5b) is disposed in a space inside the lower end net.
The aquaculture system according to claim 1, wherein the mooring unit (1) comprises: tube holders (11) which are radially disposed at regular intervals along an upper peripheral edge of the aquafarming cage (2); and a buoyant tube (12) which is connected to an outside of the tube holders (11) in a concentric circle shape,

wherein the tube holders (11) are configured such that a plurality of tube rings (11a) for connection of the buoyant tube (12) are integrally formed with a lower side of a support frame (11b), and an assembly end (11c) for assembling the foothold (13) and the safety rail (14) protrudes from an upper side of the support frame (11b).
The aquaculture system according to claim 3, wherein the mooring unit (1) further comprises: tube holders (11) for bumper function which are connected both to the buoyant tube (12) and to the tube holders (11) assembled with the foothold (13) and the safety rail (14), and radially protrude at regular intervals; and a buoyant tube (12) for bumper function which is installed in a circular shape along the tube rings (11a) of an outside of the tube holders (11) for bumper function.
The aquaculture system according to claim 4, wherein a hanging aquaculture rope (8) hung in water is mounted to the tube holders (11) for bumper function.
The aquaculture system according to any one of claims 1 to 5, wherein the cage frame (6) is divided into a plurality of steel pipes (17), and assembly flanges (17a) for assembly between the steel pipes (17) are formed in opposite ends of each of the steel pipes (17).