GB2462691A

GB2462691A - Fish farming system

Info

Publication number: GB2462691A
Application number: GB0815500A
Authority: GB
Inventors: Ivor Edward Holme
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-08-23
Filing date: 2008-08-23
Publication date: 2010-02-24
Also published as: GB0815500D0

Abstract

A fish farming system comprising a large circular tank 1 having a central pipe 5 which supports a number of discharge pipes 7. A sediment drain 3 takes water and fish waste to a settling tank 10, a filter unit 11 and a sump 13. A recycling pump 14 supplies pressurised water to the discharge pipes which provide oxygenation and a false current for the fish/trout. The base of the tank can be sloped to assist the draining and filtering function.

Description

Large Fish in a Small Pond The main problems with Fish Farming are:- 1) The area required for the construction and operation can be large.

2) Ideally running water is a requirement for the removal of waste.

3) Oxygen levels need to be kept high especially for trout farming as levels drop at night.

This invention is suitable for both large farming operations and small domestic/garden installations.

Specification

Construction:-The invention consists of a circular tank (1) which may vaiy in size dependant on the operational requirements of the Fish Farm.

The tank (1) has a floor (2) which slopes towards the centre of the tank. At the centre is a sediment drain (3) with an outlet pipe (4) which may be above or below ground. A large support pipe (5), its lower end being perforated (6), encircles the sediment drain (3). At the top of the support pipe (5) are the discharge pipes (7) these are perforated along their length on one side only (8). The discharge pipes (7) are mounted above each other in pairs thus allowing them to pass through the support pipe (5). The number of discharge pipes (7) may be up to eight dependant on requirements. The discharge pipes (7) are interconnected at their ends inside the support pipe (5). The outer ends (9) are blanked off and supported from the ground. The outlet pipe (4) connects to the settlement tank (10) and filter unit (11). The outlet pipe (12) from the filter unit (11) is connected to a sump (13) which contains the recycling pump (14). The outlet from the sump (13) is connected to one of the discharge pipes (7) thus completing the water cycle.

Operation:-The tank (1) is initially filled with water, the mean/average level being determined by the height of the inlet aperture of the settlement tank (10). The water, due to gravity, passes through the perforated lower end of the support pipe (5). Any fish waste which has collected at the centre of the tank (1), due to the sloping floor (2) is carried out through the sediment drain (3). The water plus sediment flows via the outlet pipe (4) to the settlement tank (10). The heavier sediment remains in the settlement tank 10) and the clearer water passes into the tilter (11) where it is filtered further. The filtered water now exits via the outlet pipe (12) and discharges into the sump (13). The sump is *1 (2) partially filled with water and the ingress of additional water from the filter unit (11) lifts the float switch of the recycling pump (14). The recycling pump (14) pumps the water from the sump (13) up to the outer end of one o the discharge pipes (7). The pressurised water, due to the interconnection of the discharge pipes (7), is fed to all of the discharge pipes (7) .the pressurised water flows out of the perforations in the discharge pipes (7) spraying the surface of the water in the tank (1). This provides the oxygenation of the water to meet the requirements of the fish. Due to the water being discharged from only the one and same side of each discharge pipe (7) a false circulating current is set up within the tank (1). This current, dependant on discharge rate, can be up to several miles/kilometres per hour. The false current in the tank (1) copies the natural current that the fish would experience in a stream. The fish will line up and swim against the current, this improves their health and stimulates the growth of the fish, especially in trout farms.

The false current, in conjunction with the sloping floor (2) of the tank, aids the collection and removal of fish waste via the sediment drain (3) and outlet pipe (4). The balance of the whole cycle of operation is controlled by the inlet aperture of the settlement tank (10). The rate of outflow from tank (1), the volume of filtered water being fed to the sump (13) and the recycled volume of water being pumped to the discharged pipes (7), is thus controlled. The relative height of each part of the system is critical in order to ensure a smooth and effective operation.

This invention works equally as well for both large farms, with tanks several metres in diameter, holding hundreds of fish/trout and small domestic units with only a dozen or so fish/trout.

Fig 1, 2&3 refer. p