The object of the game is to solve puzzles and earn coins to set up and decorate a virtual aquarium. Using in-game currency the player is able to purchase different species of fish, decorations, and "comfort" items to make the environment more pleasant for pet fishes. Filling all of the three meter gauges measuring the progress will unlock one of the trophies: bronze, silver, or gold. Adorned and themed tanks can be used as a smartphone screensaver.
Levels are based on a standard for "match three" mechanics: the player swaps two adjacent gems to make matches of three or more. Each of the rounds takes place on a different grid and poses a challenge earning every golden tile by matching gems over them at least once. Some of the tiles are locked and have a different color; to unlock them the player should match gems over a couple of times. When three or more objects are matched simultaneously, one of the bonuses appears: firecrackers, depth bombs, dynamite charges, or lightning. The puzzle board should be cleared before the time limit is over, otherwise play returns to the aquarium rather than progressing to the next level. The platform also provides mini-games, holiday-themed upgrades, pearl tournament challenges, and 3D-simulation of a scuba mask which allows the user to dive into the deep sea. By 2019, Playrix changed the gaming concept to "freemium", in which various currencies such as diamonds can also be purchased in the app.