What Kind of Fish Can Live With Red Swordtail Fish?

Red swordtails are a color variant of the common swordtail, Xiphophorus hellerii. Oddly, the other common name of this species is the green swordtail, since the wildtype has a greenish coloration. Selective breeding produced the red swordtails. Red swordtails make good community aquarium fish, with some caveats.

  1. Community Fish

    • Red swordtails are considered community aquarium fish. This means that they get along with most other aquarium fish of the same size. Swordtails will get along with any fish that do not bother them. Small, peaceful fish like tetras, small cichlids and catfish make great tank mates for red swordtails.

    Concerns

    • Despite their mostly peaceful demeanor, red swordtails' water preferences limit exactly what tank mates you can consider selecting other fish to share their aquarium. Swordtails prefer hard, somewhat alkaline water. Any fish that shares an aquarium with swordtails needs to be able to thrive under these conditions. Additionally, since male swordtails have long tail fins, you should avoid fish with reputations for fin-nipping, like barbs and freshwater puffer fish. Other than these, most fish can comfortably live with red swordtails.

    Other Swordtails

    • Red swordtails are schooling fish. In the wild, swordtails live in groups for protection. As a result, they tend to feel unsafe when kept without other members of their species. However, swordtails tend to establish a pecking order within their schools, with a dominant male. You should always keep swordtails in a ratio of 1 male to 2 females, since males tend to pick on each other.

    Other Livebearers

    • You should also avoid keeping red swordtails with other, related species of livebearers. Many fish in this family can crossbreed and produce undesirable hybrids. You should not keep red swordtails with other species in the genus Xiphophorus, including other swordtails and platys. Additionally, even guppies may be closely enough related for this concern to come up.