Instructions
Read the fish species tips in the Encyclopedia, which are represented by a picture of a library on the main menu screen. Some species have specific requirements, such as not placing them with active or aggressive fish species. If you fail to meet these requirements, your fish will be less healthy.
Purchase at least one male and one female of the same species. Look for the male or female symbol on the fish information box in the Marine Pet Shop to determine the fish's gender before you buy it.
Click on the starfish at the bottom of the main menu screen to open the game options. Select the fish icon on the right side of the options screen to view the mode, and change it from "Lazy" to "Expert" mode. Fish will not grow or breed in "Lazy" mode.
Feed your fish regularly to help them grow. The fish are babies, or fry, when you purchase them from the Marine Pet Shop. When the meter next to the ruler is full, your fish will be adults and thus able to breed.
Change your aquarium water regularly to keep your fish healthy and in breeding condition. Watch the water quality meter of the fish icon when viewing your aquarium. Click and hold the mouse button on the water bubble next to the meter to change the water and increase the quality.