Heat cable + temp gun

[The Serpent Merchant]

Thanks for the link! I'll be doing some research on that gun to figure out just how accurate it is.

Do you think that the prob under the tub will give a good reading as to what the inside bottom of the tub is?

No, the probe under the tub will consistently be a few degrees above the actual inside of the tub, but this is where your thermoSTAT probe should be for safety reasons.

The 412L has an accuracy of +/- 4 degrees F