Why can't I use a UTH on a plastic tub ? I have 3 or 4 friends who do it without problems and have talked to many others who do it as well. I'm not sure what the actual type of plastic is but for the full day I ran the UTH on it there was no negative effects. Maybe there is something I'm missing but is it any different than a breeder using flexwatt ? I figured I would cut out all of that work with the foil and lamps and just use a tub.