Now what.

[boggs]

So i buy a cardnial to go with the cardnial i already have. And he won't let him go anywere in the tank. He has already bit a little of his top fin. I tried to take the new one back and the LFS said i sould bring back the first one i got because he is going to be aggressive towards all the cardnials i put in there with him.

Do you think I can set up a small tank and put the big one in there until the new one gets settled?

 

[fsn77]

It sounds like you might have 2 males. The larger one is probably mature enough to mate, and may not tolerate another male in the tank. If so, it's quite possible that they will not ever live in peace with each other. Ideally, it would be best to purchase a female and hope they pair up, but cardinals are very difficult to correctly sex visually.

 

[boggs]

What do i look for to identify a female? Anyway I never would have gotton one if I would have read the "sticky" for new fish for the beginner first. It says these should be keep "solo or in mated pairs in smaller tanks." Well i guess ill have to hunt down a female. But i don't think the LFS will take this one back with the fin messed up.