Plenty big enough if for 1 female, I like to keep 3/4 females to 1 male in a breeding tub, and when I see babies, I will take the female that is on the babies most and take up to 15 babies for that individual mother and place them in a birthing tub (well bringing up tub) that way the bringing up tubs arent always full of just single does with no babies.
The females appear to be happier on their own than with others running about, especially without the male present (in most cases),
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