Do leeches kill fish?
As the name implies, these harmful leeches feed on the blood of fish and do not stop sucking their blood until the fish dies. Fish leeches are long, warm-like predators that are most commonly introduced in an aquarium through worms.
What eats leeches in water?
Many species of leeches can exist in any one water body. Most are predaceous, feeding on worms, snails, fish eggs and aquatic insects. Others are scavengers, and only a small minority of leeches suck blood from warm-blooded animals.
How do you kill leeches in freshwater?
To exterminate leeches, drain your pond, remove fish and plants, clean the mucky bottom with a pressure-cleaner and then rinse it with diluted bleach. For a week keep the plants in bleached water and the fish in a tank. Then fill your pond with clean water and add the plants and the fish.