UTH heater for Aquarium vs Reptile tank???

[Motörcrab]

We recently purchased a 75 gallon aquarium off Craig's List to house 3 md/LG PP's and 6, now 5 md/lg Strawberries. We have approximately 7" of substrate in the tank. There is an 11" X 48" Ultratherm located on the back of the tank (from top of glass to top of substrate) with 1/2" foam insulation covering the entire back glass of the tank (17" X 48"). Currently the regulator is set at 86, the probe is located on the left wall at the front corner at substrate level and is currently reading 82.7. Another temperature gauge is in the center of the tank half way between the top of the tank and the top substrate. That gauge is reading 88. We also have third gauge located at substrate level at the right front corner. that is reading 84.

I am wondering if anyone has ever done any research on heat loss with an UTH heaters on thinner glassed reptile enclosure compared to thicker glassed aquariums? With using the UTH going through 1/4" glass will this be adequate in in several months when my house temperature drops several degrees in the fall and winter months? I can always add more heaters and more insulation to the other walls if need be. I'm just trying to be pro active now before it may be an issue later.

Is it safe to say the tank is currently approximately 85? With the regulator being set at 86 I believe this to be acceptable, even though the probe is reading 82.7.

Am I overthinking this or is this reason for concern come October when my house temperature drops?

[wodesorel]

So long as the UTH is pumping out enough heat, the thicker glass on an aquarium will create more of a greenhouse effect inside. Insulating the pad well is usually enough to reflect most all of the heat into the tank through the glass even though it's thicker.

[Motörcrab]

Thanks, I was thinking it would more than likely be ok since glass is not a very good insulator. I just wanted to be sure there wasn't a loss comparable to using UV light bulbs through glass or screen. I do have an 11" X 17" Ultratherm on standby if needed.