Koi Swordtail Care Guide
Xiphophorus hellerii var. Koi · Freshwater Fish
What Koi Swordtail look like
The Koi Swordtail is a domestic color morph of Xiphophorus hellerii selected for red-white koi-style patterning. Males show the lower sword extension; females are larger and swordless. The koi name refers only to color pattern.
Behavior & temperament
Koi Swordtails are active, social livebearers that need open swimming room, plants, and hard stable water. Males may be assertive, especially in cramped tanks. Mixed-sex groups breed readily and fry may be eaten without cover.
Diet & feeding
Koi Swordtails are omnivorous livebearers. Feed flakes or pellets, spirulina foods, blanched greens, daphnia, brine shrimp, mosquito larvae, and occasional bloodworms. A varied diet supports color and breeding condition.
Behind the name
Koi refers to the ornamental red-white pattern; swordtail refers to the male caudal fin extension.
Plan your tank
Check the numbers before you buy: tank volume, a stocking plan, cycle progress, water changes, and your ongoing care routine.
Keeping Koi Swordtail?
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