Bubblenest breeders and mouthbrooders can be left in the tank until they stop caring for the young. Livebearers can be allowed to give birth in a dense thicket of plants or plastic spawning grass, so the babies can hide until the mother is done giving birth and is removed. A breeding tank also is good because it can be kept clean. Eggs and fry need very clean water to hatch and grow. There are also no adults around to compete with the babies for food.
Many breeders use a bare tank with only a sponge filter as filtration.
Debris and extra food are easily seen and siphoned off daily. Frequent water changes can be done on the tank, as there are no other fish around to stress. Another solution is to allow fish to breed on yarn mops, a plant, or a piece of slate or glass in the community tank. The eggs can then be moved to the breeding tank to grow. This works well for angelfish, catfish, and Australian rainbowfish.