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compatibility

Compatibility checker

Assess any two organisms in the catalogue against each other, with the reasoning, the concerns and the conditions shown.

Pick two organisms. The assessment is derived from stored traits when you do — it is not a lookup in a compatibility chart, and it will tell you where the evidence runs out.

Formula

  • Assessment is derived from stored traits by the compatibility engine, not from a lookup table.
  • Environmental overlap: temperature, pH and hardness ranges are intersected; a narrow or empty overlap is a factor.
  • Predation is evaluated in both directions using stored risk levels and adult size ratio.
  • Behavioural factors: fin-nipping against vulnerable fins, territoriality, breeding aggression, zone competition, activity mismatch, flow and substrate needs, diel pattern.
  • Verdict = worst factor severity, subject to counts: one major factor is a poor match, two are incompatible, one moderate factor is conditional.
  • Minimum footprint = larger of the two requirements, uplifted where spatial-pressure factors are present.

Assumptions

An estimate whose assumptions are invisible is indistinguishable from a guess.

  • Both animals are assessed at adult size.
  • The tank is adequately filtered and cycled, and the water is stable.
  • Group size requirements are met for both species.
  • The assessment is for the pair in isolation; a third species can change the outcome.

Limitations

Where this calculation stops being reliable. Read these before acting on a result.

  • Individual temperament varies, particularly in cichlids and in bettas, and can override a favourable assessment.
  • The engine reports 'insufficient evidence' rather than guessing where trait data is missing. That is a real answer.
  • A verdict is not a guarantee. Compatibility is a probability statement about behaviour, and AquariumHQ separates confidence from conclusion for exactly that reason.