Red Swordtail tank mates
Xiphophorus hellerii
5 rated pairings from the Red Swordtail care guide. Compatibility here means water, temperament, tank zone and adult size all line up — the note on each card says why. Red Swordtail needs at least 20 gallons on its own; every companion adds to that.
Excellent matches
3 · Same water, complementary zones, no conflict.
Guppy
Poecilia reticulata
10 gal min · 2" adult · Peaceful
Similar size, peaceful temperament, and identical water parameter requirements make them ideal companions
Platy
Xiphophorus maculatus
10 gal min · 2.5" adult · Peaceful
Fellow livebearers with compatible behavior and water needs; can interbreed but generally coexist well
Java Fern
Microsorum pteropus
Hardy plant that provides shelter for fry and helps maintain water quality without being uprooted
Good matches
2 · Compatible with normal care — watch space and numbers.
Neon Tetra
Paracheirodon innesi
10 gal min · 1.5" adult · Peaceful
Small, peaceful schooling fish that thrive in similar water conditions and add visual interest
Gold Mystery Snail
Pomacea bridgesii
5 gal min · 2" adult · Peaceful
Peaceful algae eater that occupies different ecological niche and poses no threat to swordtails
Planning this tank?
Run the whole stock list through the calculator — it checks bioload and schooling numbers, not just pairings.