How to Raise Black Swordtails

Native to Central America, Swordtails are tropical, live-bearing fish, that, full-grown, are approximately 4-inches in length. Although the females have a rounded tail fin, the males are spectacular with a long sword-like fin extending from the bottom of their tails that can grow to the same length as their bodies. They have been bred in many different colors, but Black Swordtail fish are one of the few truly black aquarium fish and so, are truly sought after. (Reference 1)

Things You'll Need

  • Two female black swordtails with perfectly clear fins
  • One male black swordtail with solid red fins
  • Two large long tanks
  • Breeding tank with lots of planted cover
Show More

Instructions

    • 1

      Feed your fish live food like earth worms, blood worms and shrimp brine to speed up the breeding process. (Reference 6) Set your tank up for ideal mating by keeping the temperature between 77 and 80.6 degrees Fahrenheit with a ph between 6.8 and 7.8. (Reference 5)

    • 2

      Allow the male to breed with the females. You will know a female is pregnant and almost ready to give birth when she develops a dark spot behind her stomach and looks like she is going to burst.

    • 3

      Remove the pregnant female to a breeding tank and wait for her to drop her fry. She will usually give birth in the morning at the bottom of the tank, and will drop up to 80 babies. (Reference 1) Remove the female back to her original tank once she has given birth as she is likely to try and eat her young. Offer lots of plant cover in the breeding tank so the babies have the opportunity to hide before they are consumed.

    • 4

      Wait for the new specimens to begin showing their sexes. It can take upwards of a year for the males to grow the swords indicative of their gender (Reference 3), but you can speed up the process by feeding them a combination of brine shrimp and spirulina algae. (Reference 5) Start a new tank with your best Black Swordtail specimens, a male and two females, with the characteristics you desire.

    • 5

      Feed your fish live food to speed up the breeding process and follow steps 2 through 3 again. Once your new fish start to show their sexes, you should have lots of high quality Black Swordtails to choose from.