I am currently in the process of building a coop for my seramas. It is fully insulated and has a thermostat that controls the temp; it is ~ 3'W x 3'L x 6'H Where my question lies is in the nesting box configuration. I want to fit several nesting boxes into the little space I have but do not know the recommended size to make them. 5"x5" boxes would work perfect for the space I have but not sure if this is too small. Any input would be welcome as well as any other ideas for my coop.