5 Month old Chinese Water Dragon

Question
Thank you in advance if you can answer these questions for me.  I have tried to find this info online but have had not luck.

Can a Chinese Water Dragon sleep under water??  Or is this a sign that he may be sick??  

We have a 55 gallon tank half water half dry land for him.  We have his UV lighting across the entire length of his cage.  If we put the fixture at the back of his tank.. will he get enough UV light.  Total UV is 80 watts... we have two 40 watts bulbs in the fixture.

One more question... How hot should the hot side of his tank be?

Answer
We have numerous articles on heating and lighting on our site http://www.reptileapartment.com Basking area should be 95 with the background or ambient temp of 85-88. Water dragons do not sleep underwater. As far as the lighting is concerned with the UVB are you using a tube or spot type bulb for UVB? I would also recommend for more in depth information to contact our Vet http://herphousemag.com/herpetoculture-house-staff/dr-sean-mccormack/