START WITH YOUR FAVOURITE FISH
Compatibility is more than a yes or no. Start with a complete social group, find shared water conditions, allow adult swimming room and understand the behaviour the calculator cannot predict.
A betta does not need other fish for company. A solo, planted tank is the simplest starting point. If you want companions, choose for the individual betta’s behaviour as well as shared water needs and enough space.
Compare companions →
Build the neon tetra school first, then select peaceful companions that share its water needs. Small adult size alone does not establish compatibility: predators, fin nippers and unsuitable water still rule out a combination.
Compare companions →Start a guppy community with water chemistry, fin safety and a plan for breeding. Choose peaceful companions suited to your measured water, rather than buying fish just because they look small and colourful.
Compare companions →Two species may share water needs but still run out of space in your particular aquarium. Our examples make the tank dimensions and quantities explicit, and preserve any model warnings. Every added group deserves a fresh check.
Choose a complete plan by tank size →Companion-selection guidance is curated and awaits expert review. Read our sources and review policy.