Sometimes too many snails can be a problem, even for those who like to keep snails in their killifish tanks.
However, for elimination of the pests it isn’t always necessary to sterilize the tank, or to resort to strong chemical anti-snail treatments.
“When I used to breed killies (mostly Aphyosemion australe) casually in planted setups, pulling out the fry from time to time, I used one of two biological control agents to periodically kill down the snail populations,” says Bruce Turner. “Those agents are called Gambusia affinis and Fundulus chrysotus.“
You can put some of these small snail-eating fish in with the adult killies, or you can take the killies out of the tank for a few weeks while the snail eaters do their job.
The system “works very reliably,” Bruce says. “But I learned early on to use only male Gambusia, or only one sex of F. chrysotus per tank, or else the control agents would eventually kill or outcompete” the killifish.
– G.C.K.A. Newsletter, November 1999