I would get a thermometer and make sure you are acurately measuring the temps before you try and adjust them. You wouldn't want to be wrong in assuming the temps and accidently cook her
Once you have a thermometer, if it reads that the hot spot is lower than 90 you can add an UTH or put a higher watt bulb on the tank to raise the temps.
Wax worms and pinkies are both used to fatten up leos but the problem is thats exactly what they do, they add fat, not necessarily many nutrients or other healthy things. Its sort of like eating twinkies...they will of course help you gain weight, but not healthy weight. Waxies and pinkies should be used as treats only, or for females after they lay their eggs or extremely malnorished individuals. You must first get to the root of the problem as to why your leo is not gaining weight, this will help you to be able to effectively fix the problem. You can use waxies to help add a little weight but only use them in moderation.
I would start by getting a fecal run and posting a pic when you get back home. If the fecal is positive, treat for parasites and then see if she gains weight. If the fecal is negative you may want to set up an appointment with a good herp vet to have her evaluated to make sure she is in good health and there are no other issues causing her to not gain.
Another good thing to do is to buy a digital scale so you can keep a close record of her weight. I try to weigh all my animals on a weekly basis to measure any weight gains or loses. Mapping the weight might help you to see a pattern in her gains or losses.
I would definately start with a fecal nad probably an appointment and then try to feed her more. Also, if the temps are too low this may well be affecting her appetite, check the temps and adjust them if necessary.

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