Pacu tank mates
Colossoma macropomum
5 rated pairings from the Pacu care guide. Compatibility here means water, temperament, tank zone and adult size all line up — the note on each card says why. Pacu needs at least 500 gallons on its own; every companion adds to that.
Good matches
2 · Compatible with normal care — watch space and numbers.Striped Raphael Catfish
Platydoras armatulus
50 gal min · 9" adult · Peaceful
Nocturnal bottom-dweller that avoids competition; tolerates similar water conditions
Rope Fish
Erpetoichthys calabaricus
55 gal min · 15" adult · Peaceful
Large, peaceful bottom-dweller that occupies different tank zones and has compatible temperature requirements
Use caution
3 · 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 may compete aggressively for food; only suitable in very large tanks
Banded Leporinus
Leporinus fasciatus
55 gal min · 12" adult · Semi-aggressive
Comparable size and habitat needs, but both species are semi-aggressive and may conflict as they mature
Glass Catfish
Kryptopterus vitreolus
30 gal min · 4" adult · Peaceful
Peaceful schooling fish but may be intimidated by pacu aggression; requires very large tank to minimize conflict
Also recommended alongside Pacu
Species whose own guides list Pacu as a tank mate.
Fire Eel
Mastacembelus erythrotaenia
80 gal min · 36" adult · Semi-aggressive
Arowana
Osteoglossum bicirrhosum
250 gal min · 36" adult · Semi-aggressive
Clown Featherback
Chitala ornata
200 gal min · 39" adult · Aggressive
Florida Gar
Lepisosteus platyrhincus
200 gal min · 24" adult · Aggressive
Ornate Bichir
Polypterus ornatipinnis
90 gal min · 18" adult · Semi-aggressive
Peacock Bass
Cichla ocellaris
200 gal min · 24" adult · Aggressive
Pike Cichlid
Crenicichla sp.
55 gal min · 10" adult · Aggressive
Red Tail Catfish
Phractocephalus hemioliopterus
1000 gal min · 48" adult · Aggressive
Red-Bellied Piranha
Pygocentrus nattereri
100 gal min · 13" adult · Aggressive
Tinfoil Barb
Barbonymus schwanenfeldii
75 gal min · 14" adult · Peaceful
Zig-Zag Eel
Mastacembelus armatus
55 gal min · 24" adult · Semi-aggressive
Planning this tank?
Run the whole stock list through the calculator — it checks bioload and schooling numbers, not just pairings.