Design criteria for turnkey fish rearing system

Design Criteria that must be met to provide a viable fish farming system-

2014-01-07

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A.) It must be capable of producing fish in sufficient quantities to meet the nutritional demands and provide income-producing potential for a typical Haitian family of four on their own property.

B.) It must be package able (un-assembled) in a durable shipping container and transportable through rugged terrain to areas where it is needed; weigh <150 lbs.

C.) The labor to operate the system must be <30 minutes/day.

D.) Components must be simple, repairable and operable with

minimal training, and be configured to minimize theft.

E.) Ideally the entire system would be manufactured in Haiti.

F.) The system would require minimal input of fresh water and

have the capability of providing nutrient rich water for crops or clean water for human consumption.

G.) If provided on a micro-loan basis the system should be capable of providing a 2 yr ROI.

H.) All components of the system should have a 10-year life span and be immune to possible damage by sunlight, animals (goats etc), weather disasters etc.

I.) The system must be safe to operate.

J.) The purchase price for the system must remain within the range of typical “small-scale” fund raising organizations and be easily marketable to agencies currently operating in Haiti.

Targeted Performance/Production –

•The system will be capable of producing at least 25 pounds of fresh fish/week (retail value average $2.00/lb)

• All filtration equipment is driven by low-pressure air (no electricity in water)

• Maximum water replacement = 5 gal/day

• Maximum carrying capacity 250 pounds of fish

• Required surface area 100 sqft

• Water capacity 700 gallons

 

Configuration of Current Design

The rearing tank is constructed from a “frame” of galvanized steel hardware cloth (1/4” mesh) with a liner made from vinyl billboard material, rubber or heavy plastic. The hydrostatic pressure of the water keeps the tank walls upright and secure. As time and resources become available the outside of the steel mesh can be covered in mortar to create a Ferro-cement tank. Life span of liner is about 10 years.

Tank cost = less than 50$

(Note) this technique can also be used to make much needed rain water storage cisterns

Dry bamboo cut into small rings has proven to be a wonderful bio filter material. The plastic barrel is filled with bamboo rings and bacteria that detoxify fish waste adhere to the bamboo and filter the water as it is pumped through the plastic barrel.

Drum & hardware cost = ~40$

(The barrel is also used as the packaging container to allow easy transport of the disassembled system into remote areas.)

Solar Panels (60 watt) +two 12volt batteries and charge controller supply power to a small air compressor that pumps water through drum filter and aerates the water.

Cost = $770.00 U