Watch the tank: every fish earns coins by itself, there is nothing to click. The top bar shows your coins, income per second, pearls and aquarium level.
Open the Shop to spend coins. Tabs: Fish, Plants, Decor, Upgrades, Themes. Each extra fish of the same kind costs a little more; plants and decorations are bought once. Upgrades raise income, extend the offline reserve and make events more frequent — every card shows the current effect and the next level.
Catch events when they appear: tap coin bubbles, spots on the glass and the drifting chest. A rare visitor must be touched before it swims away to join your collection.
Tasks give three calm goals at a time and pay coins, sometimes a pearl.
Controls: mouse or touch, no keyboard needed. Tapping the water nudges nearby fish aside, Esc closes dialogs. Progress saves automatically and keeps building while you are away.