How to Breed Molly Fish in an Aquarium

Breeding and raising your own fish adds a whole new dimension to keeping an aquarium and mollies are a good species to start with. Mollies are hardy little fish and even beginners can successfully breed them in one aquarium. The females give birth to live young, which do not require special food. All you need to do is segregate the babies from other fish in the tank, including their parents, to prevent the babies from being seen as lunch.

Things You'll Need

  • Live food
  • Finely chopped vegetables
  • Net breeder
  • Aquatic plants
  • Small plastic container
  • Flaked fish food
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Instructions

    • 1

      Feed the adult mollies supplemental live food such as Daphnia (water fleas) and chopped vegetables such as cucumber to improve their condition for breeding. A ratio of two females to each male is the best for breeding.

    • 2

      Watch for the females becoming pregnant, and have the net breeder ready to install in your tank when the mollies give birth. Either attach it to the rim of the tank or let it float freely.

    • 3

      Add a few floating plants to the net breeder and a bit of a bushy aquatic plant to form hiding places.

    • 4

      Scoop up as many baby mollies as you can with the plastic container and transfer to the net breeder. Those outside the breeder may or may not survive.

    • 5

      Crush fish flakes between your fingers to feed the baby mollies. Rubbing the flakes produces a fine powder suitable for the small fry. Feed both the fry inside the breeder and any outside.

    • 6

      Release the fry into the main tank once they are over 1/2 an inch long -- usually after four to six weeks. You can release them earlier but there is a chance they will be eaten.