I often hear a 10 gallon tank as the minimum size for full grown adults.
I've been doing a lot of looking at hoggies recently and am trying to find a good size tub in the area of 24x12 floor space, but I often wonder if people don't use sweater boxes (roughly 16 x 12 i think? 15x13?) for hoggies.
Hopefully someone with more experience will chime in, I'll be keeping an eye on this thread myself hoping to hear more answers.