Scratch this comment - the other thread had a link to UK UVB report which was dead on accurate. Polished aluminum reflector can intensify UVB output 6x! Lesson learned at my house.
MP
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i'd like to re-open this thread as I have a related problem I could use this communities assistance. My beardie is 4 years old, solid eater, no changes what so ever but one - its UVB lighting. My original UVB floursecent fixture was powered by a ZooMed 24" 10.0 UVB ReptiSun, 20 watt mounted over the screen top of a 40 gallon breeder tank. A 100 watt basking light and another 100 watt ceramic heat element completed the set up with broad temperate graident and lots of perches and hides. UVB and basking lights were on for 10 hours/day giving me a healthy pet for the past 4 years.
The 24" fixture went bad so I selected an 8" dome fuxture with a ZooMed ReptiSun 10.0 UVB 26 watt compact flourescent (looked good since it had a 1 year guarantee). Within 48 hours my beardie became almost comatose, not eating with one eye barely opening. I went through a list of potential issues (e.g., bad food, parasites) then recalled the change in UVB lights. I turned off the new compact 26 watt flourescent and my beardie came back to life in 48 hours. He ate a huge number of crickets today so he's back (yeah!) but very strange.
So here's the question - The UVB rating was the same (both 10.0 UVB), but the wattage increased from 20 watts to 26 watts. Has anyone seen/heard of "UVB over load"? Could the dome fixture have "magnified" the UVB? Any ideas welcome.