ok ive just got my rack system set up with flexwatt and i just wanna make sure that its all right i have a tstat hooked up to my heat tape and i was told by some people to put the probe on the heat tape but when i took temps in the tubs it was only like 80 on the substrate and like 83 under it(on the hot side) where should i place my probe and how do i need to measure my heat i have a temp gun and thermometers in the tubs