How to Breed Zebra Danios

Zebra danios are among the easiest tropical freshwater fish to breed. Zebra danios are one of a small number of tropical fish that mate for life. According to BadMansTropicalFish.com, it is very rare for the paired male to mate with any other females. They are egg-layers, and will eat their hatchlings (called "fry")---and even their own eggs---if you give them the opportunity. As a matter of fact, if you have a mated pair of zebra danios in your aquarium now, it is very likely they have already mated, but have eaten all their children! Keeping this in mind, you need to use a method of breeding that will separate the parents from the eggs as soon as possible after they hatch.

Things You'll Need

  • A separate breeding tank (minimum five-gallon capacity; 10-gallon capacity is better)
  • Tubifex worms
  • Frozen or fresh brine shrimp
  • Marbles or large-size gravel for tank substrate
  • Liqui-fry fry food for egg-layers
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Instructions

    • 1

      Condition your breeding pair of zebra danios with the best food possible so they can more easily withstand the stresses of breeding. Feed them white worms (tubifex) or brine shrimp (fresh or frozen) twice a day for about one week before breeding (reference 2).

    • 2

      Set up a breeding tank. This tank should contain an aeration and filtration system and should be "cycled" using some adult zebra danios. These adults should be transferred to the main tank once breeding commences. The breeding tank should contain either large gravel or marbles as the substrate (the material lining the bottom of the tank). This coarse material gives the eggs a lot of void spaces to drop into after they are laid. This way, the parents cannot get to the eggs to eat them before you even realize they are there! Some people like to use plastic breeding tanks that fit inside your aquarium, but this can get kind of messy and unwieldy, because you still have to keep the parents separated from the fry until the fry are big enough (about 10mm to 12mm long) to survive in the tank without being eaten. So you may as well use a separate tank in which to raise the fry.

    • 3

      Put several zebra danios into the breeding tank (making sure you have a selection of both females and males). Within a few hours, you should notice spawning activity.

    • 4

      Once a few hours have passed (or when you see fry sticking to the sides of your tank), pull out all the adults and return them to the main tank.

    • 5

      The eggs should hatch in a day or so. The fry look like tiny little black lines sticking to the sides of the tank. If you don't see any fry after a couple of days, you can try again after your mating pairs have been rested and reconditioned as described in Step 1 above.

    • 6

      Do not feed the fry while they are still clinging to the sides of the tank. Wait until they are free-swimming. Once the fry are free-swimming, feed them with a special food called liqui-fry for egg-layer fry. It's designed to be ingestible by very tiny mouths. It's better to feed a tiny amount several times a day than to feed a larger amount once a day.

    • 7

      Start feeding the fry dry food made for egg-layer fry after the fry are at least seven to 10 days old. This food should be finely ground flakes or other food made especially for fry.