About FishCompat

Free calculators — tank volume, stocking, and fish compatibility — built on one open engine and backed by a species database with structured, sourced parameters. A browsable species encyclopedia is on the way. Everything works without registration.

Every species parameter is compiled from at least two independent, species-specific sources and stored with the source list and check date. We never invent water parameters, and every calculation is documented on the Methodology page. If sources disagree, we take the conservative range.

FishCompat is an independent project run by an aquarist, built in the open and improved continuously. There is no big company behind it — which is exactly why every page has a “Report an error” button: readers who spot a mistake are our review board.

FishCompat is reference information, not a substitute for professional advice. Fish are living creatures; use our numbers as a well-sourced starting point, then observe your own tank.