Red-Bellied Piranha tank mates
Pygocentrus nattereri
5 rated pairings from the Red-Bellied Piranha care guide. Compatibility here means water, temperament, tank zone and adult size all line up — the note on each card says why. Red-Bellied Piranha needs at least 100 gallons on its own; every companion adds to that.
Excellent matches
1 · Same water, complementary zones, no conflict.
Good matches
2 · Compatible with normal care — watch space and numbers.
Bristlenose Pleco
Ancistrus sp.
20 gal min · 5" adult · Peaceful
Bottom-dwelling scavenger that avoids piranhas; helps maintain tank cleanliness without competing for food
Striped Raphael Catfish
Platydoras armatulus
50 gal min · 9" adult · Peaceful
Nocturnal bottom-dweller that occupies different water zones; armored body provides some protection
Use caution
2 · Works in the right setup; read the note before combining.Silver Dollar
Metynnis argenteus
55 gal min · 6" adult · Peaceful
Similar size and water requirements, but predatory nature of piranhas makes this risky; only in very large, heavily planted tanks
Pacu
Colossoma macropomum
500 gal min · 42" adult · Semi-aggressive
Large, robust fish that can coexist with piranhas in spacious tanks, but requires 200+ gallons and careful monitoring
Planning this tank?
Run the whole stock list through the calculator — it checks bioload and schooling numbers, not just pairings.