The aim of Nemo’s Reef is to build a section in the ocean where Nemo and his friends can live and play in. Nemo and his dad, Marlin, have to put together a reef attractive enough for different species of fish to come and live on. To do this, several tasks and quests need to be completed. Completion of these quests results in gaining experience points and/or Sand Dollars. You can also use real money to buy Pearls. These can be used to speed up building of structures or purchasing special items for your reef.

Like any city-building game, structures need to be constructed in order to attract residents. But instead of buildings; corals, rocks, seaweed and decorations are needed to house the fish. Different species prefer different structures; so structures have to be constructed and placed accordingly.
To start playing all you have to do is download the game, which is free, and keep an active internet connection. Once the game starts, you will have to choose a username or just allow the default name to be selected.