Gecko not eating or growing

Question
QUESTION: Our young Gecko stopped eating a couple weeks ago after trying to hand feed and etc.  The vet suggested separating her from the other Gecko which we have done.  She still is not eating but drinking from her dish.  I keep seeing the crickets that were given to her a few days ago and she will no longer eat meal or wax worms.  Is there any hope for her as she is very small.  The vet said she seamed alert and eyes bright, he did notice that her liver was dark due to not eating.

ANSWER: Well, I would ask what the heating parameters are first of all,  also what type of Gecko are we speaking of and what is the enclosure set up that you have in place answering these will help me to ascertain the correct answers for you.

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QUESTION: We use a bulb that was suggested by Petco.  We have a Leopard Gecko.  She is in an aquarium with a house and water dish.  I've been counting the crickets that I feed her so I know if she is eating and according to the count she still isn't.

Answer
I understand that its a bulb but I need to know what the exact temperature of the enclosure is as this is most likely the cause of the Leopard Gecko not eating.  I would like to know what the basking temperature is as well as what the ambient temperature for the enclosure is.  Also what size is the tank she is in?