# Basking spot temp?



## samstar (Feb 13, 2010)

I placed the megaray 120 watts mvb 18 inches away from the basking spot and the temp reads 105f. Is that to high for my Star? From what I understand, you start loosing the uv rays when it's anything further than 18 inches from basking spot? Shoudl I reaise it to 20 inches?


----------



## samstar (Feb 13, 2010)

Sorry it's 19 inches away or 18 inches from top of the tortoise carapase, I just measured it again.


----------



## tortoisenerd (Feb 14, 2010)

Can you provide a link to the exact type of bulb you have and where you heard you need to stay closer than 18 inches? It does vary based on the bulb manufacturer and wattage (I have only heard of 100 watt and 160 watt so I'm not sure what one you have). If you cannot get the temperature suitable with the bulb, you may want to try a different wattage. I agree it is not worth it to have the bulb further away than the manufacturer suggests, not to put it too close and have it too warm. 105 is already too high. For a hatchling 100 might be ok, and for older torts 95 (these are at the top of their shell so actually the ground temp should be lower than that). I tried the 160 watt and like you I had to put it too far away. Returned it for a 100 watt and it works great. See this website for pictures of the uvb gradient at different heights and distances away from the bulbs: http://www.uvguide.co.uk/mercuryvapourlamps.htm

Best wishes.


----------



## samstar (Feb 14, 2010)

tortoisenerd said:


> Can you provide a link to the exact type of bulb you have and where you heard you need to stay closer than 18 inches? It does vary based on the bulb manufacturer and wattage (I have only heard of 100 watt and 160 watt so I'm not sure what one you have). If you cannot get the temperature suitable with the bulb, you may want to try a different wattage. I agree it is not worth it to have the bulb further away than the manufacturer suggests, not to put it too close and have it too warm. 105 is already too high. For a hatchling 100 might be ok, and for older torts 95 (these are at the top of their shell so actually the ground temp should be lower than that). I tried the 160 watt and like you I had to put it too far away. Returned it for a 100 watt and it works great. See this website for pictures of the uvb gradient at different heights and distances away from the bulbs: http://www.uvguide.co.uk/mercuryvapourlamps.htm
> 
> Best wishes.



Sorry it says 20 inches, here's the link to my bulb:
http://www.kimbosreptileworld.co.uk/megaray-120w-self-ballasted-p-145.html
Thanks for the link.


----------



## tortoisenerd (Feb 14, 2010)

Thanks for the clarification. What temperature do you get with it 20 inches away? By the way, what is your room temperature? I assume you are from a warm climate (you house is warm)? I think if you can get it no more than 21/22 inches away I'd keep it as it is probably better than any other option you have as far as UVB output (a MVB further away than recommended still has more UVB output than a tube light).


----------



## samstar (Feb 15, 2010)

tortoisenerd said:


> Thanks for the clarification. What temperature do you get with it 20 inches away? By the way, what is your room temperature? I assume you are from a warm climate (you house is warm)? I think if you can get it no more than 21/22 inches away I'd keep it as it is probably better than any other option you have as far as UVB output (a MVB further away than recommended still has more UVB output than a tube light).



Yes I live in a tropical climate where it's warm 24/7. He is outdoors but in my patio which has a roof. However no sunlight comes into the enclosure.
I moved his hut to the extreme opposite end(cool side) of his basking spot and the temp there reads between 25-32 degrees celcius with the temp reading about 40 degrees celcius under the basking spot, this way he has an option to choose how close he wants to bask under the lamp. Also the distance between the hot and cold side is about 35 inches and I again lowered the lamp to about 18 inches from substrate, I dont want to loose out on UV by raising the height anymore. From the uvguide link you provided me, if I were to raise it anymore above 19 inches using megaray mvb, the UV exposure would be very little.


----------

