I have one remaining 8+ year old common oto in a 25 gal tank. He is the last survivor of a group of 3. The other 2 died in the last year. I am now wondering if I should move him to a 29 gal with 5 zebra otos or leave him in the tank he has been all his life. I do not want to get more fish at this time as I am planning on re-doing my fish room in February and the less fish and tanks the easier the move will be. But I don't want the oto to be unhappy either. What would you do? BTW the 25 gal will not be broken down during the move, so he could stay there. But would he be better off with other otos even if they are not his kind?