I don't see why not. Mine is in a 12 gallon Nanocube by JBJ. I don't have the lid secured but he does not show any interest in leaving. I keep him well fed and he goes back into the fliter and hides during the day. So make sure he has plenty of hiding spots and he may feel secure and not want to abandon ship. You'll probably want to wait at least 3 or 4 months on your water to make sure the parameters are good. Octopus don't have any protection like fish and a lot of other inverts so good water quality is paramount. Good luck with the little guy if you get him. there's nothing like watching your octopus change colors during commercials.
Thanks! What type of filteration do i need for him? I just have a emporer 200. Is that good enough?How did your octo cost? Here did you get it? Online or LFS