The rule of thumb with a Bearded Dragon Adult is the diet over a year is 80% leafy green veggies that are high in calcium like Collard greens, Mustards, Escarole and Curly Endives. You can also add the peppers and Butternut squash for color and taste. Berries are a great treat. The live prey should be 20% of the diet and given what can be eaten in 15 mins. All food should be dusted with calcium 5 days a week and 2 days with a good vitamin. The best feeders are Silk worms, phoenix worms, crickets and roaches. If you need places to order the feeders I can supply those. Thsi is a great nutritional chart: http://www.repticzone.com/articles/fruitsandvegetablesrated.html This is for fruits and Vegetables
http://www.beautifuldragons.503xtreme.com/Nutrition.html Nutritional value of foods
Let me ask some questions and see if I can help norrow down some issues:
Can you tell me about the set up?
Heat source and temp?
UVB light? How old? Type coil or tube?
When you say full spectrum bulb is it a florescent bulb in long tube shape or a coil shape? If it is not one of the two type of bulbs I have mentioned, then you are not using a UVB light. YOu need need to get one asap! A 10.0 Reptisun tube extending the length of the tank is needed. A Full spectrum does not supply the UVB needed for a Dragon to be healthy: http://www.anapsid.org/uvtable.html Next get rid of the sand and get back to the cage carpet. The sand is very dangerous and can cause intestinal impactions, corneal ulcers and skin problems. These are links about the two worst loose substrates:
Walnut shell Graphic: http://mrskingsbioweb.com/beardeddragngrossanatomy.htm
http://www.beardeddragon.org/articles/impaction/?page=3 calci sand
The next issue is the temps are way off. The basking area should be at 100*F-115*F and in the cool area 90's. If the temps are too low the Dragon will shut down and not eat. You should be using a digital probe thermometer or a temp gun to check the temps.
We can try some first aid to rehydrate him and you will have to fix the conditions in order to get him back to normal. Please give him a 30 min soak in a 50/50 warm water and Plain Pedialyte soak. While in there gently massage the abdomen to help promote passing of stool and any sand that may have been ingested. Get the temps warmed up and get the correct bulb and he should start perking up and eating. I would have him into a Herp Vet and checked for parasites. If you need a Herp Vet please supply a city and state. Joan