Your pearsei will soon get too big for the 180, when housed with other fish, so you may need the 125 to house the SDs.
We'll see on the Pearsei. You really think one is going to get too big for a 180 with tankmates or you think the SDs are too big as tankmates? I am downsizing from 3 pearsei to 1 soon (have someone taking 1, maybe 2 in a week). I've had the cichlids Since March and the biggest is probably only 7". I keep the tank warm and do 2 40% water changes a week but maybe I'm underfeeding.

