Indoor lighting questions

[Edna]

I'm moving my Hermanns indoors soon and they will be going into a much larger indoor enclosure. More space means more lights, and I have a couple of questions.
First, reading on the tortoise library site, Madkins says I can use fluorescent tube lights but need to balance the spectrum between warm and cool lights. I have two plant lights going with warm T-5 bulbs, so if I replace some of those with cool..... Am I understanding that correctly? I like those lights because hung at a proper height above the plants they warm the area below them about 10 degrees.
Also, about CFLs. I know not to use a complact fluorescent UVB because of negative impacts on the torts. Recently a post said that all CFLs are bad. Can anyone point me to the science behind that statement? Here's why I ask: Even with the T-5s and an MVB, I still have a lot of space to light. Without the torts in there I'm lighting it with two CFLs that are in a comfortable range for my eyes, and are certainly more energy efficient than the incandescents I would have to replace them with.

 

[StudentoftheReptile]

I'm moving my Hermanns indoors soon and they will be going into a much larger indoor enclosure. More space means more lights, and I have a couple of questions.
First, reading on the tortoise library site, Madkins says I can use fluorescent tube lights but need to balance the spectrum between warm and cool lights. I have two plant lights going with warm T-5 bulbs, so if I replace some of those with cool..... Am I understanding that correctly? I like those lights because hung at a proper height above the plants they warm the area below them about 10 degrees.

Also, about CFLs. I know not to use a complact fluorescent UVB because of negative impacts on the torts. Recently a post said that all CFLs are bad. Can anyone point me to the science behind that statement?

While I don't have any precise "studies" to back it up, my understanding is that compact florescent bulbs are simply too bright/intense, regardless of their shape or design. Many keepers have observed these bulbs cause blindness in their tortoises.

Now you say "all CFLs"...I'm not sure what you're getting at, but are you implying to use a CFL that was not even designed for reptiles? If so, I would discourage this even more the reptile-specific ones.

Here's why I ask: Even with the T-5s and an MVB, I still have a lot of space to light. Without the torts in there I'm lighting it with two CFLs that are in a comfortable range for my eyes, and are certainly more energy efficient than the incandescents I would have to replace them with.

I don't know what kind of T-5s you are using, but I would careful with those as well. I used them once on some babies and they blinded my tortoises.

Personally, I prefer standard tube florescents; old school, I know, and maybe they don't last as long, but so far no one has claimed their tortoise got blind from a T-8 or T-10.

All in all, what is more convenient for you and your power bill may not be best for the tortoise. You may need to reconsider your lighting arrangement.

 

[Edna]

So the T-5s are just too bright, too? Bah!
Switching to T-8 or T-10 wouldn't be a problem, but will plants grow under them?

 

[StudentoftheReptile]

So the T-5s are just too bright, too? Bah!
Switching to T-8 or T-10 wouldn't be a problem, but will plants grow under them?

They should. People have been doing so for years long before T-5s and CFBs were invented.

 

[jaizei]

How high are the CFLs mounted, distance above substrate? What about the T-5s? I like to mount bright lights, regardless of type, at least 18-24" above substrate.

 

[Edna]

Right now, with no tortoises in the enclosure, the T-5s are 12" above the substrate, which gets me the optimum height of 10" above the little plants. The CFLs are 22" above the substrate, 10" above their taller plants. All the current fixtures are on chains, easy to raise to whatever height is wanted.
I just priced a 2-bulb fixture that will accept T-8 and T-12 bulbs and that system would not be expensive or difficult, just not sure if the light from it would be adequate.

 

[Madkins007]

T5's are generally a smaller option, but they do produce more glare than a larger bulb. I do not know if that is the issue that caused problems for Student, but I don't see any other warnings or bulletins about them.

Now- T-5 UVB lamps are a slightly different story- these can emit too much UVB if the high output units are used and/or they are placed too close. This article is tough to work though, but shows some results of different tests about 2/3rds down. http://www.uvguide.co.uk/phototherapyphosphor-tests.htm

COILED UVB bulbs have a bad reputation. The original problem was that the coating on some bulbs of one type from one maker was mis-formulated and allowed too much UV to be emitted. The maker says they fixed it, and many sources seem to agree that everything is OK.

Some people, however, claim on-going issues with coiled bulbs. Coiled bulbs are a little tricky in that they can easily emit a rather intense beam out the coiled end that may be a little more than we want, especially if used in a reflector. It is tough to find a map of the way the energy moves from the bulb- an irradiance diagram- so it is unclear exactly what is going on.

One company that still makes the coiled bulbs, Exo-terra- does not seem to say much on their site about mounting them, but I think it is very interesting that the mounts they make for them mount them sideways- which would eliminate the 'hot spot' question.

 

[Edna]

Thanks, Mark! That site has some great information about the light products marketed for reptiles.
My next mission is to find UV output information on the bulbs I have.