Tokyo-based 9003 Inc is releasing an English language version of Aquazone, a program that creates a virtual reality tropical aquarium for personal computers in which fish swim around, eat and breed. The software is already the firm’s best seller in Japan and is set for release in the US later this year and then in France, reports the Wall Street Journal. Budding aquarians begin with an empty fish tank and add gravel, plants and even ornaments that you’d find in a real fish tank, such as statues of Rodin’s Thinker and ones from Easter Island. Tropical fish of a variety of different species can be added, each with its own characteristics. Some fish are brave, while others scatter when the fish tank glass is ‘virtually’ tapped. The fish thrive if they are fed properly, but if their water filter is not cleaned regularly, or you forget to look after them regularly, they may wither and die and float to the top of the tank. And if you don’t remove the dead fish, they turn black and dirty the water. The program keeps track of your scaly companions when the computer is switched off. Users in Japan have become very attached to their fish and have bought up 13,000 copies of the program since its release at the start of last year. The company also sells additional disks that hold different fish and plant species. 9003 is now considering establishing an ‘information river’ enabling fish to swim from one computerised fish tank to another across a local network.