it's the hydrocynus forskalii. I believe it only reaches about 18 inches in the wild. They probably only get 12 inches or so in captivity. A fellew member had one for 2 or 3 years and it is a good 12 inches or so. they grow pretty slow. A 240 gallon is ideal but bigger the better.
For tankmates, I definately wouldn't suggest silvery fish. ATFs loves to attack silvery fish. You can have some large tough fish such as aros but there might be some aggression. Sometimes it works. Sometimes not. Trial and error. Some large bottom dwellers will be good too such as bichirs or catfish. Make sure that the cat can't swallow the ATF!
Just make sure the tank mates aren't too big or aren't too small. If the tank mates are big, it might eat the ATF. If it is too small, the ATF might eat that fish.
Hope it helps.