On my original design, I planned on having the 41 qts deep wise, so the rack would be around 3 feet wide. My new/current design, is to place the 41 qt tub long ways, being 3 feet wide. So basically 6 levels of 3 foot wide shelving. I only have 2 females right now, and all the additions I am planning on getting this summer are hatlings/yearlings. So I will mostly need smaller tubs to house them in.
I think I am thinking to much. I do this with everything. If I build something secure, and just put my BP's in the right size tubs, then they will be fine.