So lat week my girlfriend dropped our last ReptiSun bulb and it broke (not the glass, it would just not turn on.) so we ran to the store and grabbed a Zilla desert bulb while we waited for the new Reptisun in the mail. It has been 4 days and Herman is already starting to shut his left eye all the time.
Just an FYI to everyone these bulbs are still bad.
Not necessarily. How old was your last bulb and how far from the lamp is your basking area? An old bulb produces much less UVB than a new one and if your animal has adapted itself to a low UVB it will need to close it's eyes until it adjusts to the light. Also a Reptisun only produces about 25-30 microwatts of UVB at 12" while the Desert 50 produces 40-50 microwatts. So chances are your beardie is getting a lot more UVB from the new Zilla lamp than the old Reptisun (considerably more if the lamp was old) since the distance to the basking area is still the same (I am assuming). However it is not harmful UVB and it will adjust to it eventually. I would suggest increasing the distance between the lamp and the basking spot or reducing the number of hours the lamp is on to reduce the UVB exposure until the lamp breaks in and the UVB drops. The UVB is going to drop about 20% in the first 30 days which is normal for fluorescent lamps. After that it will decrease more gradually.
One last thing to check for is to verify that you have a new Desert 50 lamp. You can do this by looking for the UV Index graphic on the box. If it has it, it's a new lamp.
Andy
I have only had my dragon for a month period. The reptisun was pretty much bran-new. I did indeed keep it the same distance away (8 inches) so maybe you are right about that, but either way he was shutting his eyes and would not eat, I got rid of it and gave him my iguana's old Powersun till the resptisun arrives in the mail.
I just had to post a follow up to this. Monday my two reptisuns (encase one breaks again) came in the mail, I waited one more day for his eye to clear up, and threw in the reptisun... he is 10 times more active than he was with the zilla bulb.. the proper lighting does make a difference.
i have a desert 50 and use it for secondary UVB one of my beardies cage, its not under the basking spot there i have a powersun MVB but in any event she will go and sit about 6" under the desert 50 every once in a while for short periods of time, it definitely outputs UVB and does not appear to bother her eyes.
one thing you should keep in mind is that if the bulb is brand new it will output much more than normal for the first 100 hours or so