Reptile & Amphibian Forums

Right now I just keep my UVA/B bulb on top of the tank... So it's pretty much 6 inches away from the water. My turtles swim at the top sometimes but sometimes stay near the bottom.

My question is how far does the UVA/B ray have to be to be effective for the turtles?

Different bulbs have different recommended distances (the one I use says 8-10 inches, I have it around 7) but after 12 inches, I don`t think a turtle would really benefit. Water filters a lot of UVB rays and if you have your light on a screen, it will also. (I read that a screen`s holes should be one-eighth of an inch or larger for a turtle to get adequate UVB rays through it.)

I use a clip lamp for my UVB coil bulb and aim it directly at the basking platform from about 6-8 inches away. My turtles love basking, and this way I'm sure they'll get plenty of DIRECT UVB while they bask.

That`s exactly what I do. (He is basking under it as I write this.) Are you using an ESU coil lamp?

I can't say that I do since I'm not sure how one looks. I'm basically using the ones that go on top of the tank that fit exactly perfectly. If 6-8 inches is good enough then I'll keep using that, thanks for the input. Oh the bulb I got is Repti Glo 5.0 and it doesn't say how far it should be.

Someone posted on this forum before that I was keeping the bulb to close to the turtles and that it would damage their eyes.. and that it needed to be farther away to fully get the UVA/B rays so thats why I posted.. hope theres more replies if others have opinions

Hmmm...I`ve never heard of a conventional UVB light hurting their eyes (I`ve wondered at times what, if anything, it`s doing to mine, though). The only thing I remember reading a while back(I can`t remember where, sorry) is that there is an imperceptible flicker with the UVB light (fluorescents in general?) and there was the question of damage from them staring at it. (My turtle kept staring at the UVB light when I first got him.) I remember someone saying that by using a UVA light (like a regular light bulb) along with the UVB would help mask the flicker. I don`t know how true it is, but that`s what I`ve been doing, since the regular light provides the heat for the basking area as well. (He doesn`t seem to stare at the UVB anymore.) I do know, though, that with the UVB, the further away it is, the less your turtle benefits. About being too close, I don`t know, I do think that the 6-8 inches is a good guide.

Yes, I use the ESU Super UV coil-lamp! It's energy-efficient too.

I use something very similar, but it`s from a Japanese maker (I`m in Tokyo). It`s energy efficient too--20 watts, but gives the output of 80 watts. I really like it. If I was in the States, I would use the ESU coil lamp like you do. (It gives 3% UVB and I think Reptisun 5.0 gives 5%, but I read the 3% is sufficient, and I think my turtle really benefits from basking right under it.