If the OP is still around, or anyone else who has gone this route, I have a couple of questions regarding the tubs.
What size tub do you usually use for the females to lay in? The standard size or a larger/deeper one? Do you breed in the tub and just let the whole process happen in the same tub or switch them to a larger/deeper tub later? I'm fascinated by this.
All of the breeding and incubation took place in a 41 quart tub. The size isn't important as long as they feel secure. I wouldn't switch them to a new tub later because that might cause them to abandon the nest.