1. Choose fish that is not healthy and sick, of the type that can adapt to the water plant. Fin fish with the bright colors are in contrast with the water plant that is green.
2. Adjust the amount of fish with the capacity of the pond. Should not too much, because some species of fish is very easy to breed.
3. Eat fish according to its needs. Too much food residue in the bottom of ponds can decrease the quality of water.
4. When you have a sick fish, separate them immediately because the fish can affect the other.
5. Check the pool water quality regularly and periodically clean the pond. It is a good idea use the pool water filtration system.