Compatibility

Compatibility is not a yes or no. AquariumHQ derives an assessment from stored traits — temperature, pH and hardness overlap, predation in both directions, fin-nipping, territory, zone competition, flow and substrate — and shows the reasoning alongside the verdict.

How to use this

4088 pairings have their own page, chosen by the opportunity engine from the organisms most widely kept. Start from a species below to see everything assessed for it, or assess any pair in the catalogue on demand with the compatibility checker.

Start with one animal

Each species page lists every pairing assessed for it, grouped by verdict, with the dimensions that decide its pairings counted across all of them.

Shrimp (3)

Fish (84)

Snail (3)

Crayfish (1)

Red swamp crayfish90

Pairings to avoid

Combinations the engine assesses as a poor match or worse, most-contested first. These are the ones most worth knowing before a purchase.

Verdict distribution

Across every pairing with a published page. A catalogue where almost everything came out compatible would be evidence of a broken engine rather than a peaceful hobby.

Verdict	Pairings	What it means
Incompatible	1447	Should not be attempted.
Poor match	1028	Workable only in unusual circumstances.
Conditional	695	Workable if the stated conditions are met.
Generally compatible	640	Requirements align with little or nothing to qualify.
Compatible	278	Requirements align with little or nothing to qualify.