Bearded Dragons color

Question
I am a new beardie owner and have a few questions. He/she is about 6-7 months old and we have had it for abou two weeks. At first I had him in a 20 gallon tank but he didn't seem to enjoy it so I have since moved to a 40 gal tank. I use a 150 watt basking bulb for his basking area and elevate it about 6 inches off the top of the screen top. I also use a 60 watt daylight bulb on the other end of his tank to keep the ambient temp in the low 80's and to allow for UVB. I also have a heat pad under the tank that is on all the time but he is found of it mostly at night. It too is on the same end as his basking area. he has several items to get up on in the basking area as well as things to hide under in both sides of the tank. The temp at the hottest part of his basking area is about 105 and he moves up and down as he needs. about a week ago he shed and his color was great. He was a nice brown and tan color. Some days he seemed darker then others hence the reason I have done so much to make sure that the temps are just as I have read in every area and believe me I check and recheck to the point my wife has gone mad. haha I use a vita sand or calci sand as a substrate which was recommened from the pet store and was told to me that it would NOT harm my beardie if he ingested it. He has a nice size water bowl that he can crawl in and out of, specially designed for that so he doesn't drown. I am gut loading his crickets and he eats so many of them. He also loves mealworms but when I feed him them I don't use a dish I just drop them in with him and he tears them up. I clean his poo out of the tank daily and makes sure he has clean water. His color seems to have turned to a light yellow color but he still seems normal with eating and activity. My wife says he just looks a little washed out and that concerns me. I am a first time beardie owner and very concerned. This dragon has me hooked and I want to do everything that I can to make sure that he is ok. Any suggestions that you can give me will be greatly appreciated. I know I have just said a whole earful but I am desperate and worried about our new baby. Please let me know if this is normal and what I need to do different if anything. Thanks so much.

Jim

Answer
Hello Jim,

Good that you upgraded his tank size to a 40 gallon tank instead of a 20 gallon.  
What are you using to measure the temps with?  Is it a stick on type of thermometer, or a digital probe or temp gun?  
The heating pad, you should turn that off during the day when the basking light is on he will get overheated with underbelly heating & overhead heating at the same time.  If you would like to turn it on for nighttime, that is fine.
That is quite a bit of wattage for a 40 gallon, at over 200 watts.  
What type & brand of UVB are you using, is it a flourescent tube bulb or a compact or coil light?  
Unfortunately, the calcium based sand is not really recommended.  It can cause impaction because the calcium based sand hardens up like cement & it is very difficult to pass.  The best sand is to use the washed & sifted playsand because it doesn't clump up.  
Go easy on the mealies as they are fatty & do not offer a whole lot of nutrition.  I would only feed mealies a few times per week & limit them to no more than 6 or so.  He is still growing so he needs his food, so crickets are great.  

Tracie