Aquarium Fish Compatibility Checker

Pick the fish, shrimp and snails you want to keep together. You'll get a verdict for every pair, with the reason: temperature, pH, size, aggression or fin-nipping. Covers 72 popular freshwater species.

Pick two or more species to see if they can live together.

Popular species

Cherry shrimp tank mates14 compatible speciesBetta fish tank mates39 compatible speciesDwarf gourami tank mates51 compatible speciesGuppy tank mates46 compatible speciesBristlenose pleco tank mates53 compatible speciesFancy goldfish tank mates1 compatible speciesHarlequin rasbora tank mates50 compatible speciesMolly tank mates58 compatible speciesNeon tetra tank mates40 compatible speciesPlaty tank mates51 compatible speciesTiger barb tank mates29 compatible speciesAngelfish tank mates26 compatible speciesOscar tank mates0 compatible species

All 72 species →

Common questions

Tank size guides

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FAQ

How does the compatibility checker work?

Each pair is checked against shared temperature and pH ranges, adult size (can one eat the other?), temperament, territorial behaviour, fin-nipping and shrimp/snail predation. The worst result sets the verdict. Full methodology.

Where does the data come from?

Water parameters and sizes come from Seriously Fish and FishBase, cross-checked, with other published care guides for shrimp, snails and goldfish. Every species page lists its sources. Data last reviewed 2026-11-04.

Note: Compatibility depends on individual temperament, tank size, decor and how fish are introduced. Our verdicts use conservative rules applied to published care data (see methodology). They are guidance, not a guarantee. Quarantine new fish and watch for chasing, torn fins or hiding.