Fish Breeders and Fish Hatcheries
If you wish to breed fish, use a fish breeder to control the environment and make sure tiny, defenseless fry don't get eaten by other fish. (Larger refugiums and isolation units are also available for multi-purpose isolation.) Consider a sponge filter for tanks where you'll raise your fry, as they can get sucked up into other filters. You'll also find brine shrimp hatcheries here to raise your own for premium fry food. Don't forget brine shrimp eggs and fry-friendly fish food!