Using LEDs

Hello everyone
I am new to this site I have three beardies and i am always looking at ways to same energy. I am building a new enclosure for my two females . The specs at this time are 6'x3'x2'tall. I was thinking of using UV LEDs for the UVB supplement instead of a HO T5. I have built LED fixtures in the past for my reef tanks and was hoping to do it for my girls. Has anyone tried this or do you think it is doable? Thanks
Jeff

You need to be very careful about the wavelengths that are put out by the UV light. Short wavelength UV (below 290nm) can cause serious harm. (Most of) the UVB tubes that are available have been designed carefully and tested to prevent emission of low wavelength UVB. For this reason, I'd stick with a more traditional UVB source.

The LEDs i could use are 305nm to 315 or they make one that is 365nm to 370. Any comment on that.

That may be OK then. Do you have a UV meter to test the outputs? I'd try to use a combination of those. The 295-320nm ranges are involved with the process of vitamin D3 synthesis but so are the 320-350nm ranges (UVA) so you'd want something in place to cover that area as well. The higher wavelength from 350-400nm may be included in their vision and includes beneficial UVA. Ideally you'd want to create a steadily increasing output between about 295nm and 350nm to imitate sunlight as closely as possible. I get this info from the bulb testing results published by uvguide.co.uk which is a trusted source in my opinion.

Another thing to consider (and to have a meter for) is the intensity of UVB at various distances. Without having prior testing done, you'll want to take measurements with your custom setup to see how far it's projecting useful UVB rays and set the mounting distance accordingly.

Part of the problem with LED is the narrow spectrum they have. "White" UV lights probably aren't as 'white' to reptiles as they are to us, since their visual response range is different. Unfortunately most lights, not just LEDs will suffer from this since they are designed to look good for humans.


As far as I know there are no UV LED lamps recommended for reptiles. That's not to say its impossible of course. To do such a thing I'd think you would certainly want to invest in a UV meter (or a set of them) to make sure you are getting the output and ratios you need. If you are really savvy with lighting and electronics it might be worth joining the Reptile Lighting group on facebook and chatting with some of those folks to get a better feel for what all it would entail.

((Looks cooper beat me to this part)) To quickly address wave lengths...the process that starts D3 synthesis in the skin is active between 290-315nm and peaks at 297nm. Part of the regulation system also relies on UV light and is active between 290-325nm. The visual response to UVA in some reptiles is around the 365nm range. paraphrased from uvguige.co.uk

Ok so my next lighting question is in a 4x2x2 enclosure is a 4ft 52 watt T5HO too much light? At about 15" from the light Im getting a reading of 110 on my solar meter i think its the 6.2 is that too much light? If so would changing it out with a 2ft T5 HO light be ok? My dragon seems to be doing well no eye squinting. The guy i have been talking to and who I bought two of my dragons from used the same size bulbs as I do but used the standard t5 fixture not the HO is his enclosures. I now have his old enclosures and i get a reading of 35 or so at about 15 inches. Both tests where done with new bulbs. Im kind of a perfectionist when it comes to the care of my Kids(pets)I have no kids.
Any Info Helps
Thank you
Jeff

It should be OK as long as you provide hides and shade areas further away from the bulb. I have a 36'' tank and a 34'' T5. I have it offset so it sits toward the front of the tank. When I measure the output at the back of the tank and down to the floor (18'') I get readings between .5 and 1 UVI with my 6.5 Solarmeter. There are several hides and shade areas that get to 0. The basking spots are elevated so they receive UVI between about 4.5-5 which is a good level for basking. I've found that there is adequate variation to allow for self regulation and it hasn't been a problem. I considered putting a piece of plastic up over half of the fixture or putting the mesh top back on the tank to intercept a bit of the UVB but I haven't felt it is necessary for now. Making the most out of landscaping makes a big difference. If I had it to do over, I'd probably go with the 22'' so there is a nice gradient moving toward the cool side of the tank and I'd center the light a bit more, but it's not a change that needs to be made right away.

Thank you cooperdragon
Do you think i should change out the other enclosures? You wouldnt happen to know how to or if you can convert my UVB number to come up with the UVI?

At 1/3 of the readings I'd probably change out the fixtures so you can take full advantage of the T5's output or at least fit them with a reflector. The 35 uW/cm2 that you're seeing is consistent with output of a T5 with no reflector. The 110 uW/cm2 reading you're getting is consistent with a T5 w/reflector.

You can't change the output of your 6.2, it's designed to show total UVB output which is useful for measuring the total power/output you're getting. It's actually quite helpful for measuring decay and comparing output between lamps. If you want to read the UVI then you'll need to pick up the 6.5. I don't know that the readings have a direct relationship and can be converted as UVI is unitless. There is more info about the meters available here http://www.uvguide.co.uk/usinguvmeter.htm

Here is a pic of my male and female im trying to breed this year and then all three in a bath And this is the enclosure I built

They are very nice looking dragons =). I like the looks of the enclosure too. Good combination of shady areas, climbs, and basking platforms.

Thank you.
So i read over that uk website way out dated the study was done in 2004to2005 im not sure if t5Ho where even out. Im going to do some experimenting with the 23 watt t5 ballast and the 54 watt T5ho ballastboth with reflectors and w/o and I even bought a mvb to do some testing on. From what i under stand there is a formula to convert uvb to uvi I think. But I think its just a estimate. its UVB/30
no that can very a lot. if its right my uvi is around 3.6. Is your 36 fixture a HO?

Yes, I have this http://www.lightyourreptiles.com/34-t-5-ho-fixture-high-output-with-arcadia-d3-12-ho-bulb/ which is essentially a T5 HO grow light fixture w/reflector.

Do you use that brand of bulb as well? Have you ever used zoomed 10.0?

Yes, the Arcadia bulb came with it as a kit and it's excellent. I haven't used a ReptiSun 10 T5 but have tested the T8. For the T5 results I use what Frances Baines reported and posted in the UVB Meter Owner's Group.