what is your thermostat temp set at?

All of my stats are set at the temps I want in the tub...If the stat says 88...It's 88 in the tub...Otherwise it defeats the purpose of having a thermostat!

Believe it or not, mine is set at 85F, and it is 90 inside hottest. This is because the heat source I use is 11 inch and put longitudinally, not horizontally (one tub per level) so the wires are in from the back. The central part of the flexwatt between the A/C is hotter than the edge, and through trial and error before I put snakes in, I found that with the probe on the end of the flexwatt, the middle part was 90 in the tub when about 85 on the edge.

There is no magic answer here what you need is to place your probe on the heat source and play around until you get the desired temps in the tub.

Depending on the tub, heat source, type of rack or individual room temps people will set there t-stat differently I have rack where I set the t-stat at 85 to achieve 88 in the tub some where I set the t-stat at 92 to achieve 88 in the tub.

Play around you will find the right setup for YOU.