If you have the thermostat probe sitting on the bottom of your tank over the uth you need to remember the temp on the substrate will be alittle lower. Depending on what you use the temp maybe much lower. Check the substrate surface temp with a IR themometer. I got back into keeping snakes recently and once i got my IR temp gun and figured out how different the surface temps were compared to the ambient temp, my habiats have now become very accurate to the correct temps and having hot and cool zones.

I live in Houston so its naturally pretty humid. I have a forty gallon tank with a uth that is not stuck directly to the bottom. It is very near but doesnt touch. With that and about 3/4 inch of shavins for substrate it is spot on 90°. I do have other lamps.

I hate heat and keep my apartment at 68-70 at all times. With that i have to use a ceramic heater and set of low watt heat bulbs(they also are my day and night cycle). Even with the uth on the glass it didnt give me the proper temps. I added the extra help and placed the uth near the glass again, instead of on, and now my temps and humidty are perfect.(compared to most care sheets.)

I do use light stands for a proper distance and made a cardboard cut out that fits the screen with a window for the heat and light to pass through. I covered that with foil and that helps trap my heat and humidty.

I now have a zone from 78 to 91 in the tank.

I have yet to find an accurate hydrometer for tanks so i use my calibrated one for my cigar humidor. With my overkill setup my numbers are spot on without a thermostat and therefor have no flux in temps.

Im not against a thermostat i just haven't shelled out the money for a good one. The way i have mine set up the uth is unable to overheat my tank. Which i prefer.

You can go to any hardware or office supply and buy little rubber pads/buffers to raise your tank just alittle. They are to prevent slipping or scratching of tabletops or furniture. They come in all sizes and materials.

I prefer the naturalistic look and have live plants and a pretty complex set up. The plants will help keep humidity up if you are having a problem with that. I mist each morning.