Quote Originally Posted by JLC
I'm having trouble following the exact situation you have there. Does the warm side get hot enough? But the heat-mat alone isn't keeping the "cool" side warm enough?

If the tub has a lot of floor space (relative to the heat-mat you have attached to it) you may want to consider a second mat to keep the cool side warm.
Sorry..

The mat stat is set at 87F but the temp at the hot end is only reaching 75F.

I dont use the mat for the cool side.. I use it to cover / 1/2 of the underside of the tub.

Shall I cover half of the underside of the tub?