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[SlothHead]

Maybe i am reading this wrong or something, but one point that doesnt seem to be stated, you do need a warm and a cool end.

So there are many variables here.

If you are running a thermostat, what sort is it, Dimming or pulse? Does it have a probe, or is it one that is built in internally?

What are you keeping in there?

How big is the enclosure?

What are the standard temps in the house?

Where did you put the thermometer when you were testing the temps?

These are just the start of the heating dilemma. Without knowing these, you may be producing temps of 40degrees under the lamp and only 25 at the other end. that is just a hypothetical.