Production of fish

Fish farm ponds systems
Earthen fish ponds are commonly used for land-based aquaculture systems. Fish pond size is determined by the projected fish stocking density, the size of farm and the quantity of water from the water source. Kenya has conventionally recommended 300M2 pond size for Fish Farming Enterprise and Productivity Program (FFE&PP) .  The fish pond is stocked with 1,000 to 1,200 fish fingerlings for a grow-out of 6-10 months. .

Recirculating aquaculture systems (RAS)
Recirculating aquaculture systems (RAS) are the newest form of fish farming production system. RAS are typically an indoor system that allows farmers to control environmental conditions year round. While the costs associated with constructing a RAS are typically higher than either pond or cage culture, the economic returns RAS are high making it a worthy investment opportunity. Recirculating systems advantages includes: greatly reduced land and water requirements; a high degree of environmental control allowing year-round growth at optimum rates; and the feasibility of locating in close proximity to prime markets. Currently Recirculating aquaculture systems (RAS) investments are being done in urban areas around Nairobi, Kiambu, Mombasa, Nakuru, Tharaka Nithi, Nyeri and Kisumu Counties.

Cage culture production system
The need for the use of cages to rear fish in inland waters is an increasingly becoming popular method of fish culture in Kenya recently. Cage culture initial investment costs are relatively low and simple technology and management methods. However, these water-based culture methods differ from land-based operations such as ponds and raceways in that they are open systems, where interaction between the fish culture unit and the immediate environment can take place with few restrictions, and they are often sited in publicly-owned multipurpose water bodies. Thus any impacts may lead to a conflict of interests.

Raceway fish production system
A raceway, also known as a flow-through system, is an artificial channel used in aquaculture to culture aquatic organisms. Raceway systems are among the earliest methods used for inland aquaculture. A raceway usually consists of rectangular basins or canals constructed of concrete and equipped with an inlet and outlet. A continuous water flow-through is maintained to provide the required level of water quality, which allows fish to be cultured at higher densities within the raceway. Trout fish species are commonly culture in raceways around Mt. Kenya, Aberdare Ranges, Mau Ranges and Mt. Elgon.

Land area  projected land for fish pond construction should be relatively level.  A slope of about 1% is ideal. Such an area should not be prone to flooding,pollution in runoff from adjacent land. If possible, the land must be slightly lower than the water source, so that the ponds can be filled by gravity rather than by pumping.

Water supply for aquaculture are surface waters (streams, springs, lakes) and groundwater (wells, aquifers). Wells and springs are generally preferred for their consistently high quality water. A good water source will be relatively free of silt, aquatic insects, potential predators, and toxic substances, and it will have high concentration of dissolved oxygen.

Soil  should be comprised of good quality soil, with little or no gravel or rocks either on the surface or mixed in Some soil with higher clay content—preferably between 30 and 40%—should be available nearby. In absence of good soils, farmers may consider using dam liners or concrete during fish ponds construction.

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