Habitat - Indoor :: UVB Requirement

[Kallistos]

Hello,

I've been searching online for awhile, but haven't found much information on this topic. Does anyone know how much UVB a red ear slider needs? I mean in uW/cm2 or any other form of actual measurement. I think it'd be really cool if we could create a chart of UVB output of different bulbs/tubes out there. I already see that under lighting there is a section titled "Measuring UVB Output" so I must not be the only person that is curious.

Thanks!

[Kallistos]

Wow, well this site is pretty cool, it shows the uW/cm2 UVB output of a ton of bulbs, now I'm just curious how many uW/cm2 (microwatts per square centimeter) of UVB output RES need.

[SpotsMama]

I haven't seen where anyone's published how much, specifically, a RES needs. However, the rule mentioned on this site (as well as other sites) makes a lot of sense. The ideal would be to provide approximately the same about of UVB for your turtle as he would get in the wild. Since RES are native to the southern USA, then the theoretical target amount of UVB would be the amount a wild RES would get in one of our states in the deep south.

Here's a site which lists some sample natural sunlight UVB measurements from different parts of the world:

http://www.uvguide.co.uk/uvinnature.htm

[Kallistos]

Well, assuming that RES bask primarily during noon'ish, even the most powerful MVB's produce the same UVB as the Florida sun at noon in December...which is a about 250 uW/cm2. These fluorescent/compact bulbs are only putting out 3-10 uW/cm2 which is kind of disturbing.

[DavidY]

Oh yea, you will never get an off-the-shelf light bulb that can come close to the sun's full strength even in the temperate zone. But the sun never shines full strength for 12 hours a day. And even at noon it doesn't shine through all the time because of cloud cover. I also wonder if the turtles shells get darker where they receive more UV in order to block the excess radiation that they don't need. Where turtles kept in captivity with lower UV basking lights might stay lighter colored. ?

[Kallistos]

That's an interesting question. People on this board say that Reptisuns are fine, they only give off 10-20 uW/cm2, and then on the other hand MVB's are giving off exponentially higher amounts of UVB.

[SpotsMama]

I wouldn't say the Reptisun 10.0 compacts are fine. Some of them at least seem to be excessively strong - so much so that if one is placed too close to the turtle it seriously hurts the turtle's eyes. I think that UVB measurements are somewhat tricky. I'm not aware that turtles that bask out in the sun ever have problems with swollen eyes like they've had with some of the Reptisun 10.0 compacts.

[DavidY]

...Don't forget that there have been some who had problems with the Reptisun 5.0 compact flourescent bulbs causing eye irritation too. If you use these bulbs you need to make sure to follow the manufacturer's instructions carefully. They're posted here on this forum...http://www.redearslider.com/forum/viewtopic.php?t=9236

[scripta_elegans]

I think that the amount of time a captive vs. a wild turtle spends basking has to be figured into the equation too. I would guess that pets spend more time basking, which means that they get more UVB by legnth of exposure instead of stregnth of exposure.

[marisa]

I would think that if you used a reputable UVB or MVB light and kept it on for a sufficient amount of time, your turtle would determine how much to bask and would get the amount of UVB he needs.