The Best Way To Breed Fish Ever wondered how to get your fish to breed? Well, here's a little secret from my 30 years in the fish raising and aquarium industry. It's all about temperature control. You see, many fish species respond to a sudden drop in temperature by going into breeding mode. So, if you've got a fish that's proving difficult to breed, try this. Research the ambient water temperature of their natural habitat. Mimic this temperature in your aquarium for a while, then suddenly drop