Willie's MegaRay bulb is on 12 hours,and focused on his basking place. But he's all over the place in his enclosure. Well out of the range of his bulb. He's walking and climbing all over. Yay! You Go, Willie! But, I worry he's not getting enough hours of rays. What are the recommended number of hours?
If the required MINIMUM is 30 mins outdoors in the natural sun at noon...and your bulb emits 5% of the sun's UVB emissions (using the reptisun 5.0 as an example)...then the math is there to do...
For those that use the Mega Rays, the time required under them is much less! The emissions from this bulb are equivelant to the sun on an overcast day which still provides a wonderful amount of UVB. With just a guesstimate I would say the minimum requirement for this bulb is about 3 hours of intermitent basking under the Mega Ray.
Any math whizzes out there?? ;D
Last Edit: Nov 5, 2004 19:06:58 GMT -8 by prism_wolf
A lot of those who are using a combination of tubes and mvs are moving the tubes into the cooler area of the shelf...so when they move to that spot to cool down they are still getting UVB. Put those in Will's fav cool-down spot... ;D
Gehrman's study demonstrated that an iguana (in this case spiney-tailed) can be exposed to 12 hours of 100-300 uW/cm2 and maintain proper blood hydroxyl levels.
In the case of Strong MV lamps like Mega-Ray, a 6 hour time period is sufficient to maintain proper levels.
In the case of weaker tubes, 10-12 hours is necessary.
Iguanas will move in and out of the UVB as their body tells them it is necessary. So, as long as you provide a non-direct UVB place for the iguana to retreat to, all is well and very much like their natural environment.
A few things to take into account: Day/night cycle for iguanas is still 12/12. So, be sure that there is an alternate natural or artificial light source for 12 hours per day.
Be sure your iguana is maintained at an optimum heat gradient in the enclosure. If you are using Mega-Ray EB which gives off no (little) heat (be careful NOT to touch a hot bulb ), you will need an alternate heat source after turning off the Mega-Ray EB. In the case of the SB, the same holds true, but is more pertinent since the SB gives off heat, so turning it off effectively turns off the heat source.
Even if you burned the Mega-Ray for up to 12 hours a day, Gehrman's study showed that it will not harm the iguana.
If you choose to cut the Mega-Ray off after 6 hours, and you provide alternate heat, you can save on lamp-hours and more than likely extent the life of the Mega-Ray.
Last Edit: Dec 16, 2004 19:09:09 GMT -8 by dominick
Post by prism_wolf on Dec 17, 2004 17:18:30 GMT -8
Hey Dom~ I was mistaken. I haven't read the study. I was remembering the most recent theory article with Juju whom BobMac recently corresponded with in which Gehrmann reviewed favorably on the theory of to much UV-B (in the higher ranges of the UV spectrum) creates the same problems as not enough UV-B.
I have also read Ball's study (www.anapsid.org/jamesball.html) whom also mentions Gehrmann. A lot of the info is a bit lofty, but if you know anything about the photochemical processes that take place...or don't and want to learn...this is a great place to start.
I would certainly like to read Gehrmann's study... .
Jukka Lindgren's study was indeed interesting information. It's theory that UVB higher than 305nm becomes photo-destructive was quite an eye-opener. However, he also agrees that this could very well be part of the self-limiting process in reptiles to prevent them from over procuding vitD3.
He's about to undertake another study, under Dr. Gehrmann, that will test Mega-Ray and a couple of other "heavy weight" lamps to determine overall UVB output and specific nanometer ranges.
You can find Dr. Gehrmann's study on the Meter Group files section or the Reptile UV Info site.
It's called: "Comparison of Two Artificial Ultraviolet Light Sources used for Chuckwalla (Sauromalus obesus) Husbandry."
Last Edit: Dec 18, 2004 9:10:38 GMT -8 by dominick