Mine is a pain and only eats live but wasn't even taking that until I raised my temps a bit.
Most surface temps are 80-86 with a log at 90-92. I also added a small uth that stays around 92. Mine usually stays on the cool side but after adding the uth and lowering the heat lamp raising the temp she started eating. Now if she would just take f/t.
I would check with the previous owner and see how the feeders were being heated and do it the same way.