WoW. Ignorant much??
Overhead or back heating runs a higher temperature to get the surface temperature to where you want it. This will increase the ambient temperatures.
Example in my hatchling rack I use back heat and the THG is about 96 degrees to give me a rear of the tub temperature of about 85 degrees.
All my racks running belly heat have a temperature difference of about 3 to 5 degrees between the floor temperature and the THG.
I don't know why people feel the need to comment if they don't know the answer and then get all pissy when corrected. Husbandry already has enough problems with all the he said or I heard stuff.
Knowledge is a useful thing to have, without it we are all ignorant. Now if you know better and respond the same would just be stupid.![]()