When gds (2), were small I thought it would be fun for them when they visited....they lived three blocks away, so visiting was often.......bought an average size tank, all the fixings, and let them pick out fish. Nice variety..cool at first, then fish began to die off, must replace them! Then tank needs to " really get cleaned"... And guess who had to do that. About two yrs later, girls were no longer interested, I got tired of replacing fish, so it all got dumped! Had parakeets at one time too...messy! Now just dog & cat...life is so much easier.......