Quote Originally Posted by AmericanTacos View Post
I know the UTH won't do anything for ambient air temps, that's what the CHE is for. The problem is that the UTH doesn't seem to be heating the floor at all. I'm not measuring the glass, I'm measuring the substrate and the air temps. The problem is mostly heat buildup - certain places are being heated TOO much, and the other places aren't heated enough. The heat isn't dispersing at all.
I followed that diagram when I was setting my tank up, but the thermostat probe isn't really the problem. The temp gun is my main source of measurement.
You need to take your UTH temps at the glass, if it's 88-90 at the substrate it might be hot enough to burn your bp at the glass. They can and they will get under the substrate, you really don't need half an inch of substrate in there.