Re: Fish Tank PC
An aquarium on its own requires a lot of care, throwing fish into a PC will make it even more of a hassle... I feel very sorry for the two Bala Sharks sitting inside that PC Aquarium considering the amount of room they require to properly grow.
That aside, pick a fish species that can tolerate a WIDE temperture range... You have to make sure of two things, 1, the computer heat doesn't cause the fish tank water to get hot... Two, use small fish such as cheap neon tetras. Stay away from "dirty" fish. Second, you have to figure out how to filter and aerate the water for the fish, hence the reason you want to stay away from things like Bala Sharks, and Goldfish... They are very... well, they love to poop and create a mess of filters. Last but not least, do NOT use the fish-tank water to cool the tower, you WILL cook the fish.
In all honesty, the reason it isn't done is because once PROPER research is done, most realize that doing such a thing puts severe stress on the animal, as well as once people realize the care it takes to keep them alive with-out having a PC in the mix... Most just ditch it. Oh, don't forget how heavy it will become.