From Last Day of Work:
These are your fish, and like real fish, you need to take care of them. Feed them, cure them if they get sick, breed them and make lots of babies. Fish Tycoon, though, is not just an aquarium sim. Sell some of your fish in your store and with the money that you earn, buy supplies, special chemicals and ornaments to customize your own tank. Over 400 different species of fish to discover. Your ultimate goal is to breed your fish until you discover which combinations will create the 7 Magic Fish and solve the genetic puzzle. Version 1 may include unspecified updates, enhancements, or bug fixes.