I have had Spike for about 4 months now and have been using the Zilla Desert 50 bulb. After doing some research on here I think that may be my problem. His appetite has been decreasing and he hasn't ate at all the last 2 days. He also has a bump on his backbone between his shoulder blades. I tried to take a picture of it, but it is hard to see it in the picture. I plan on getting him a new bulb because I am thinking that is the problem. I hope he doesn't have MBD. Can that be cured by switching bulbs? I don't want him to suffer. I also have a skink in a different cage that has this bulb. He seems to have lost weight and today I noticed he is missing his crickets when he strikes at them. I am afraid his eyesight is not so good anymore. Also if I can buy the ReptiSun bulbs, does anyone know if they will work in the Zilla fixtures? I hate to buy new fixtures also if the others will work.