Idle Mutant Aquarium

No two fish are ever the same.

Every fish in your tank is grown from its own genome - shape, fins, colour, pattern and glow are generated, not picked from a list. The fish you are looking at right now has never existed before and will never appear in anyone else's tank.

Merge two fish and their genes mix. Keep the blue, chase the veil tail, push for the glow. That is the whole game: not collecting three of a kind, but breeding towards the fish you have in your head.

WHAT YOU DO - watch the tank (no timers, no fail state) · merge same-tier fish to breed the next one · hatch eggs decided the moment you place them · collect pearls while the tank runs itself, and keep earning while the app is closed · spend on volume, filters, aerators and 40 decor pieces that actually change income · fill an encyclopedia of 43 trait entries, each paying a permanent bonus · take orders from local aquarists who want a very specific fish · sell to the market, catch wild visitors, clear daily tasks for shells.

WHAT MAKES IT DIFFERENT - 147 real freshwater species across 36 families sit behind the generator, so your fish look like fish. Rarity is not a lottery ticket you buy: it comes out of the genes you selected for.

COZY BY DESIGN - no lives, no energy bar, no punishment for closing the app for three days. Play three minutes on a bus or an hour before bed; it works the same either way.