I've been keeping veiled chameleons (one at a time) for quite a while. I recently purchased a Solar Meter (UVB radiometer 6.5R) that measures the UVB received at any location in the cham enclosure. I have a 24x24x48" screen enclosure. I have always placed the basking dome in the rear left corner of the cage top and the UVB/daylight 22" tubes (2 daylight, one 12% UVB arcadia tube) on top towards the front of the cage, the way everyone seems to do. The rule is that the cham, when basking, should also be getting his required exposure to UVB. But here's the problem: the UVB reading 4" below the UVB tube is 3 on the Ferguson scale, the correct intensity the cham should be getting when basking (basking temp is ±85). But the basking light is some distance from the UVB source, and the UVB under the basking light alone is insufficient (only about 0.2 or 0.3). Since chameleons are sensitive to temperature, they will instinctively move towards the basking area. But they can't sense UVB, so there is nothing to get them to move to another location to be under the UVB lamp. Both should be in the same place. But how? I can't put the heat dome (10" across) and the UVB fixture (24" wide) in line with each other, so I don't see a way to ensure that the cham gets both heat and enough UVB at the same time. It's a problem because according to my solarmeter, UVB drops off rapidly once the cham moves a few inches from the center line of the UVB light source. I never thought about this until I went out and spent $249 for a solarmeter and was shocked to see how fast UVB drops off just inches from the source. Anybody have thoughts about this?
Proper placement of basking lamp and UVB/daylight tubes
- Thread starter Gideonk
- Start date
regal81455
Established Member
You need to angle your uvb or heat lamp ( generally it's the heat; or both I suppose ) so that the heat and UV intersect at your basking location.
If you are using a 12% T5HO bulb then your uvi should be much higher 4 inches below the fixture. You would be seeing levels above 13 UVI easily at that distance. So either you do not have a T5HO fixture and bulb, the bulb is too old, the bulb is not working, or your screen material is too dense.
There is a huge drop off of UVI which is why you always want placement of your branches to line up with your UVB fixture. Most will angle their heat fixture so it is aimed at the basking branch below the UVB. This creates an area of heat with UVB. To do this you can raise the fixture up off the top of the cage to angle it.
Here is the thing... With a T5HO fixture and regular aluminum screen top of cage and a 12% bulb you would actually need easily 12-13 inches from the top screen to the branches to get a 3-4 UVI range. With a 6% bulb and the same set up you would need 8-9 inches to be in the 3-4 UVI range. This is why I said something is up with you only getting a 3 UVI at 4 inches down. It is much too low.
