I kept a couple of octos back a few years ago. The first one died after only two days, then i got a different one and it lived for a couple months until it layed its eggs. It died shortly after that. It was really cool though, it took all the tank decor and drug it into one corner and made itself a den to hide in. It would only come out to eat. He was a good pet, i really enjoyed taking care of it. If you can afford to give it its own tank, then go for it. You'll like it.