Pond Design: Tips and Trick

A good pond design is one of the first factors to becoming a successful tilapia farmer in a tropical country. At first glance a well-designed pond might appear like any old hole in the ground, in reality there’s much more to proper pond design than meets the eye.

To prove this point I’ll go over why the ponds I built in Canada, as golf course water hazards, would be absolutely terrible designs for raising tilapia in Sub Saharan Africa, and combined that with recommendations for a better design.

Size Matters

As it happens, size does matter. My golf course ponds are miniscule. They occupy a couple square meters at best, with a depth of about a foot. A pond of a couple square meters just isn’t going to cut it for tilapia aquaculture. They should occupy at least four hundred square meters and be a meter or two in depth. A spacious three fish per square meter is the recommended stocking density for low intensity systems. That means by the end of a six-month production cycle I’d be lucky to harvest six fish from the golf course. I'll need to reconsider my priorities as a fish farmer when I return to Canada.

Shape: Rectangles

My ponds are stylistic; they’re shaped like a teardrop and horseshoe. They also feature aesthetically pleasing jagged, rocky banks. These features would make harvesting a pond difficult, nets would be damaged and the fish would easily evade capture. It’s best to simply forget about the aesthetics for this project and go with a rectangular pond with shallow sloping banks. Fish won’t be able to evade the net by swimming underneath, only leaving one option for escape, a flying leap to temporary freedom.

Notice the banks of this pond; they're still pretty steep,

which makes it difficult to land a seine net

Water Source: Streams and Springs

Now that we have a general idea of the size and shape of the pond we need to think about our water source. This thought can be surprisingly overlooked. My golf course ponds are filled with water from a hose. Economically, the cost of running an electric pump in a low stocked pond, would destroy any hopes to make a profit. It’s great if there’s a reliable free source of water nearby coming from a stream or natural spring. Even more importantly these sources of water should be available year round to avoid the disastrous implications of evaporation.

This was supposed to be a pond but access to available water was overlooked.

Water Flow: Let Gravity do the Work

Planning for water inlets and outlets is essential for providing fish with optimal growth conditions and to make pond maintenance easy. An inlet can be a simple PVC pipe that connects a water source to the pond. The outlet should be a PVC pipe located at the base of the pond, with a standpipe joined to an elbow connector, making the water level easily adjustable.

Wild fish can enter ponds if inlets aren't securely covered with a fine net material. 

The inlet and outlet features are great for controlling water coming in and leaving the ponds. Restricting water that leaves a pond can help retain nutrients in water column whereas allowing water to flow through the system can improve water quality, it's a balancing game. Partially draining the pond also makes harvesting the fish an easier task. Lastly, to ensure wild fish do not enter your pond, it's best to install a fine mesh screen on the PVC inlet. Wild fish can have a tendency to impact productivity in a negative way by competing for feed, increasing the waste production in the pond and possibly eating your farmed fish.

Outlet standpipe allow farmers to control the water level in their ponds.

The concept of farming tilapia in a low intensity pond system can seem be pretty simple but by keeping these pieces of advice in mind before striking soil with a shovel could save huge amounts of time related to pond maintenance in the future.