I just saw a 74 quart tub at Target. I believe the dimensions are 44" X 18" X 6". Would this one be too big? Just asking because this would give him more room, but I wonder how difficult it would be to keep the temps where I'd want them to be?

Plus, how important is it for the UTH to cover almost every square inch of the area it is heating? What I mean by that is, I have the flexwatt that is 11 inches wide. If I put it underneath longways, there will be about 3 or 4 inches on the sides that it won't be heating if I go with a tub that's 18 inches wide. If I turn it a different way, it covers those areas, but will only heat 11 inches of the 34 inches across (if I go with the 60 quart). Not sure if that makes any sense how I'm explaining it. Anyway, thanks for the help.