I don't have anything to drill holes in the tub, I don't think cutting a hole in the top really did anything since it is sealed off completely with tinfoil, and then the duct tape over it like in the DIY sticky. And right now the humidity in Fairbanks is less than 40 all around, and it's even lower in the house so I have to do a lot to keep the humidity up.

I will probably need to have the flex watt run the entire length because it's going to get super cold here in the winter, which is soon.