✅ Fish & Coral Compatibility Checker
Add fish, corals, and invertebrates to check if they're compatible. We'll flag aggression conflicts, reef safety issues, tank size problems, and more.
Why Compatibility Matters
Mixing incompatible species is one of the most expensive mistakes in the aquarium hobby. An aggressive fish can kill $200 worth of tankmates overnight. A coral that wins a chemical war can wipe out neighboring colonies. A wrasse that seems peaceful will eat every shrimp you add.
Our compatibility checker tests your planned livestock list against known incompatibilities, tank size requirements, bioload capacity, and species-specific conflicts. It checks for aggression between fish, predator-prey relationships (like hawkfish eating shrimp), reef safety issues, schooling minimums, and coral allelopathy.
Tips for a Peaceful Community
Add the most aggressive fish last — established fish are more territorial toward newcomers. Keep only one tang species per tank unless it's 180+ gallons. Avoid mixing angels of the same genus. Provide plenty of rockwork with caves and hiding spots to reduce territorial aggression. Use our Fish Guide and Coral Guide to research each species before buying.