Workshop Module 11: Aquaculture 307If you want to use all three types of fish in your system you must:
- Introduce them in the right order:
- 1st: Herbivore fish.
- 2nd: Add omnivore fish when the herbivore fish are 3 months or older.
- 3rd: Add carnivores 3 months later.
- Have a pond which has enough room for the different types of fish -
5m x 5m or more is recommended.
Once established, the pond will mostly look after itself:
- Some food and general maintenance will be required.
- Continuously observe the health of the fish and the amount and types of fish.
- The omnivores and carnivores will control the number of baby fish, eating
many of them. This helps to prevent overstocking of the pond. But if they are
introduced too early they might eat all the other fish. - Protection for small fish is needed so that some baby fish survive (rocks, water
plants, used cans tied together, etc).
Stocking rates
- 3 fish per 1m^2 is a good for most fishponds.
- For a 100m^2 pond stock 300 fish - This is for a fishpond that has manure and
leaves added as well as some food. - The number of fish can be increased to 5 fish per 1m^2 with extra food and good
management, but the amount of food must be given accurately and a good
knowledge of fishpond maintenance is needed.
The following example of stocking rates is a good as a general guide:
- Approximately 30% Tilapia or similar local species.
- Approximately 50% Carp or similar local species.
- Approximately 20% Catfish.
About eels
- Raising eels with other fish can create problems, especially in smaller ponds.
- The eels can reduce other fish stocks.
- Sometimes eels will naturally enter fishponds from rivers or rice paddies.
- Try to keep eel numbers low and only introduce them if you are confident of
managing them well. It is better to keep them separate.