I was able to pickk up two mature Perculas for my 125 DT. I originally had two but one committed carpet suicide about 6 months ago. The single fish is doing well. Should I be concerned with having three, the two I picked up seem to be a pair. Should I look for another similar (slightly smaller or larger) for my original fish or will the three live in harmony. It's only been a day but I see no sign of agression, in fact the single fish appears to be very happy to have the company.