I'm so confused - Lighting/Heat Etc

[LilliPut]

I just got my first dragon a few weeks ago. I thought I had everything right, but now I don't think I do. He is almost 6 months old and 15" and 205g.

I have him in a 75g aquarium with lights on the top screen. The screen is made of 1/4" hardware cloth, so better for light to pass through than the usual reptile screens, but.... I bought a 48" reflector hood and have a 48" Reptisun 10.0 T8 bulb. I realize now that this T8 is pointless with his basking spot being about 14" away.

I am using a 90w hallogen bulb for his basking area and that is right on temp, 105-110. He opens his mouth ever so often to purge, so I believe at least here I'm good. However "ambient temp" off his basking spot is around 80 on that side of the tank, even down to 75 on the floor. Cool side is 75. Should I be as concerned with the ambient temps as the basking temp?

I know I need to get a new T5 bulb and this weekend we are starting a build on a crossfire type enclosure. I'll be ordering a 36" fixture/bulb on Amazon today so we can have it by Friday to hang inside his tank until the crossfire is completed. I want to make sure I'm getting the right thing in place for him now while the other is being built.

I was also thinking of making the new enclosure a little shorter to help with heating, perhaps 18" instead of 24" as the plans draw out. What is the mark for concern on being too close to a T5 bulb in the basking area. Last thing I want is to change bulbs and end up with too much UVB

I'll get it right...promise!!

 

[Taterbug]

You can add additional basking lights (lower wattage or incandecent globe in a dome with a wider spread to the light) to bump up your ambient sounds, I might do so, at least on the warm side. You can also raise the basking spot closer the the UVB, with a reflector 10" away or so should be getting a decently high UV exposure.

If you build I would not reduce the height, I actually ended up building a taller one than the 24". A solid lid will hold heat a bit better but it is always easier to make adjustments when you have more space than not enough. I would suggest a 22" T5.

 

[LilliPut]

You can add additional basking lights (lower wattage or incandecent globe in a dome with a wider spread to the light) to bump up your ambient sounds, I might do so, at least on the warm side. You can also raise the basking spot closer the the UVB, with a reflector 10" away or so should be getting a decently high UV exposure.

If you build I would not reduce the height, I actually ended up building a taller one than the 24". A solid lid will hold heat a bit better but it is always easier to make adjustments when you have more space than not enough. I would suggest a 22" T5.

Duh moment! I didn't think about additional lights, thank you!! We did try a CHE, but didn't see any change lower in the tank at all. So, you would suggest a 22" rather than 36" for a 4' enclosure? I was going to put it at an angle rather than straight across the back so I can have the basking area more in the middle of the enclosure rather than the back. Do you still think I can do that with a 22" fixture? Since you mentioned the wooden top holding heat better I think I will keep the 24" height. I really wanted to be able to do more, 18" isn't all that much space...

Thanks so much for your input!!

 

[Taterbug]

The CHE should have helped but I'll be honest I've not used them. Anyway extra lights should help as log as the beam isn't very focused like a spot light. Using a higher wattage lamp further away can also help get a bigger warm zone.

I use a 22" in my 4x2x4h and used it also in my 4x2x2, the shorter bulb will help you make a area of UV and also an area without on the cool side. They are pretty strong lights Even at an angle the 36" would shine on most of the enclosure. It would be OK if you didn't use much vertical space but then you sort of end up wasting space to keep a UV gradient it that makes sense. This may illustrate what I'm saying a bit better. The UV spreads out more than you might expect to the sides.


If you don't use a reflector the "balloon" will be smaller and not reach so far into the cage. How you plan to furnish and where your heat lamp goes may also sort of limit how far away from the ceiling the basking spot will be.

 

[LilliPut]

Have replaced the T8 with a 22" Reptisun T5 in the Nanotech fixture. I have it 12" from his basking spot. So, UVB ...check!!

Now I am confused about temps. I might should make a new topic, but I'll ask here first. I've been checking basking temps with a black and Decker gun. Pointed within just a few inches of his brick give me 113 at the hottest center. I use two bricks as his spot. I added zoomed probe digital gauge and placed the probe right between the bricks, level with the top. This is telling me temps are 128...whoa!! I'm using a 75w halogen at 12". How are the temps so different? And is this truly too hot when temp gun gives me a good temp?