yep, either way, but if you plan on getting more than one, buy all at the same time, your odds are very slim, in getting a 2d or 3d one in the tank for long, after one has already been established, we had 2, thenone died, then got a 2d and then we were going to get another, until we found out that we would probably be wasting our money, since our first would more than likely kill the new one, and this was told to us by an lfs on our way out the door, had they kept their mouth shut, they woudl have made a 50$ sale, i gotta think they wer honest, being as we actually had the fish 1/2 way to the car b4 the owner came out and said"you got one already don't you"