Decided to start a new thread just for this issue, since it was getting lost in my other post!

Long story short, I am getting my first BP in 10 days and need to get my temps right.

Specs:

20 gallon tank with mesh locking lid
Thermometer/humidity gauge (digital)
Temp gun ordered and coming
Very thin layer of eco-earth and repti bark for humidity (less than 1 inch)
Zoomed UTH for 20-30 gallon tanks (attached to thermostat) (ordered a ultratherm, just waiting on it)
CHE with wire holder, 150watts (turned all the way up on dimmer)

I have the probe from the thermostat on the bottom of the tank, with the heat pad on top of it (probe is centred). Reading 89-91.

Temp reading on other side of glass, on top of heat mat and beneath thin layer of sub is 88-90.

Ambient temp right now is stuck at 73 and that is where my problem lies.

I have all sides of the tank except the front covered in tinfoil and the top is covered in tinfoil as well, leaving space for just the CHE. Half the tank is covered by a small blanket (not close enough to CHE to be a fire hazard!)

I'm not really sure what else I can do to bring the ambient temp up.

Will post pics!