from the blog

The Basics of Breeding Freshwater Aquarium Fish

Caring for fish

September 30, 2020

Platy fry

While several species of freshwater aquarium fish breed readily under a variety of circumstances, some have specific requirements that must be met before they are likely to spawn. The basics of breeding, however, are fairly uniform among most species of freshwater aquarium fish. The first thing you must do is to select a breeding pair, or a trio for some species, and quarantine them in a breeding tank. Once you have done so, you can begin the process of conditioning your fish for breeding.

Setting Up a Breeding Tank

The size of the breeding tank should depend on the size of the fish, but ten to twenty gallons is usually sufficient. The tank should be bare-bottomed in order to make it easier to clean and it should be decorated sparsely. It is wise to provide a few hiding places like large rocks or terra cotta pots in the event that the female needs a place to rest and recover from the male’s aggressive advances. Some species – egg-layers in particular - prefer a breeding tank stocked with live plants on which they will deposit their eggs.

Encouraging Your Fish to Spawn

Maintaining a steady temperature and providing a healthy, varied diet are two of the most important elements in encouraging your fish to spawn. The temperature of the breeding tank should be determined by the breed of fish but, in many cases, slowly raising the temperature encourages breeding behavior. In some species, however, the opposite is true. Corydoras catfish, for example, typically spawn after a recent rainfall has lowered the temperature in their native habitat, the Amazon River.

Offer your fish a varied diet consisting of small amounts of live, frozen, flake and pellets foods several times a day in order to condition them for breeding. After a few days you should begin to notice courtship and spawning behavior. The male of the species will often chase the female around the tank and some fish, like betta fish, will prepare a bubble nest and collect the eggs after spawning has occurred.

Caring for Fry

Some species of fish, such as cichlids, care for their fry after they have hatched but most freshwater fish are more likely to eat their own young. This being the case, it is wise to remove the parents from the breeding tank as soon as possible after spawning has occurred. If you are breeding an egg-laying species, dose the tank with methylene blue to prevent fungus from killing the eggs. Install a sponge filter in the corner of the tank to provide filtration without putting the fry at risk for being sucked up an intake valve.

For the first few days after hatching, the fry of most egg-laying species will subsist on the remainder of their yolk sacs. The fry of live-bearing species, however, should be started on a diet of newly hatched brine shrimp or a liquid fry food such as infusoria. During the first few weeks after hatching it is important to feed the fry small amounts several times a day. Once they have tripled in size you may begin to feed them finely crushed flake foods and, as they continue to grow, move them to a larger tank.

Tips for Breeding Success

If your fish are not in prime condition, they will be unlikely to spawn. In addition to a healthy diet, clean water is essential to the health and well-being of your fish. Establishing a colony of beneficial bacteria in your tank is one of the best ways to keep the water quality in your tank high. Install an EcoBio-Stone to begin a colony of nitrifying bacteria that will help to remove odor, break down wastes, and keep the water clear. EcoBio-Stones are made of natural volcanic rock infused with beneficial bacteria that will multiply readily upon being introduced into your tank. Not only is this product perfect for the breeding tank, but it can also be used in fry tanks where power filters are not recommended due to the danger they pose toward delicate fry.