I suggest the same as Kaiser mentioned.. I have a pair of saddlebacks hosting in a carpet and in the same tank I also have a pair of maroons hosting in a sebae. I started out with one saddle back and then added a smaller one a month later, they paired up with no problem. How long have you had your perc? Sometimes it takes a day sometimes months... I guess it all comes down to which ones you want to end up to the next step you take...