MVB (very bright and very hot)

[Isa]

My fiance's cousin from the States is in montreal this weekend. We orderer a T-rex MVB 100W flood and ask her if she could bring it here. We got it yesterday and installed it and put it in a 8'' ceramic lamp fixture, yesterday night while Hermy was sleeping (and we added the 2*4 foot fluorescent light).
I already had one T-rex but it stoped working after a little while (less than 3 months), I know there is a 6 months garanty but since I live in Canada, I did not reclaim a new light since they do not ship in Canada). When that light was on, it was from 14'' from the floor and I had to put the heater on at 24C in Hermy's room if I wanted all the temperatures to be respected. After the light stoped working I put back my 100W UVA and the UVL light.
SO, the lights went on at 6AM this morning. I was already awake so I went in Hermy's room to see if everything was ok AND OMG it was so bright!! Much more than the old T-rex.
I checked the temps under the basking light 30 minutes later and the temp was 32C so it was all good. I went back 4 or 5 times and the temps was always a bit higher than the last time I checked. I put the digital termometer under the basking spot and in the shadow( because when I put the digital one under the light and not in the shadow, the temps will not stop go higher and higher). 10 minutes later I verify the temps and it was 38C. I think my old T-rex was not working properly or something because it was never that hot and never that bright. Now there is a distance of 19'' between the floor and the light. The temps are 33C under the basking spot.
Does Hermy still receive UVB since I put the light that high (19" from the floor)?

 

[Kristina]

It depends on what the manufacturer's specs are. It should say on the package. I know with my UV bulb, it says to place it no higher than 20" from the floor, but that varies from product to product. I would say he would still recieve beneficial UV up to about 24".

 

[Isa]

It depends on what the manufacturer's specs are. It should say on the package. I know with my UV bulb, it says to place it no higher than 20" from the floor, but that varies from product to product. I would say he would still recieve beneficial UV up to about 24".

On the package, it says the minimum distance should be 12''. It does not say anything about the maximum distance.

 

[DuttonWebb]

also consider the burn in time. When I first got my uvb bulb it was soo powerful, it took about 2 weeks for it to settle down a bit. It was painful to look at so I placed it very high above the enclosure, now after a couple months its perfect and I have it about 23"

 

[egyptiandan]

Like Dutton has said there is a burn in period with MVB bulbs of about 15 to 20 hours where they produce high amounts of UVB, so really shouldn't be used on a tortoise until they are burned in. After that they settle down and produce a constant amount of UVB.

Danny

 

[Isa]

Thanks to both of you

After those 20 hours, does anybody know the maximal distance I should put the MVB from the floor.

 

[DuttonWebb]

Thanks to both of you

After those 20 hours, does anybody know the maximal distance I should put the MVB from the floor.

Whats the temp of the room? I have to set my basking light closer or further depending on the air temp. the mvb is basking and uv right? just experiment to get the perfect 90ish.

 

[tortoisenerd]

I know the 100 watt Mega Ray has a minimum of 12" and maximum of 20" for useful UVB (yes you'll still get UVB at higher than this, but it's recommended for the animal that you don't place it higher). For 33C (about 92 F) at 19" away, I say that sounds about right assuming you keep the room temperature a tad on the high side (the temperature is mostly dependent on distance and ambient temperature), and the T-Rex bulb is supposed to be the same as the Mega Ray. I think my bulb is about that distance away (maybe a little closer since I do a basking temperature of 100F). They do take awhile to warm up as well as the burn in phenomena. I think for the first couple hours it is on, it'll still be warming up. That, and your room temperature might be changing with the day as well (either from the thermostat, or the sun coming in the window, or both).

Hope Hermy likes the new bulb!

 

[Crazy1]

Isa, here are two sites that tell you and show you how the lights work.
At 20" a 100 watt flood T-Rex will give you 100-150 microwatts/cm2 which is about the same amount as a partly cloudy day in So. Carolina USA This is what I have mine at for the hatchlings and they do fine. As Kate has said the recommnded min is 12" and the Max is 20" for both the T-Rx and Mega Ray.
Also the type of dome you have size and reflective material make a difference. See Domes in the second link I provided.
http://carolinapetsupply.com/uvb_output_of_bulbs.htm
http://www.uvguide.co.uk/mercvapournarrowfloods.htm#uvheatnewflood

 

[Isa]

Thanks for the replies Dutton, Kate and Robyn
I will put the light back tomorrow morning in Hermy's enclosure (I will keep it open in another room until tomorrow morning for the burn in period). I will put it back tomorrow with the 8'' ceramic fixture lamp but tomorrow afternooon, I will go buy a 10'' at home depot. Is there really a difference between the 8'' and the 10''? With the 8'' now the light is comming out a little of the fixture.

 

[tortoisenerd]

There is a pretty big difference in the 8" and 10" as the larger one disperses the heat and light to a larger radius (reducing the spot effect). Also the 10" dome is deeper so less of the bulb sticks out to annoy the humans. I remember Meg showed a photo of the Mega Ray in a 8" dome and it didn't seem to work as well as the 10" I have and is also recommended by the manufacturer.

I didn't know I was supposed to have the bulb out of the enclosure for the burn in. I guess I am lucky that we didn't have any ill effects (didn't notice it as being any brighter). I will remember that when I replace it in June! The Mega Ray also undergoes slightly different testing than the T-Rex...I believe they may let it run a little longer to make sure it's not a dud.

 

[Maggie Cummings]

also consider the burn in time. When I first got my uvb bulb it was soo powerful, it took about 2 weeks for it to settle down a bit. It was painful to look at so I placed it very high above the enclosure, now after a couple months its perfect and I have it about 23"

Hey Dutton...I just wanted to say I am very impressed with your knowledge...I didn't know that about the burn time...

 

[DuttonWebb]

hah thanks. I read the instructions that came in the box. It was weird. My light was almost a shade of purple-ish blue when I first plugged it in. Pretty sure I tanned my retinas a little bit.

 

[Isa]

There is a pretty big difference in the 8" and 10" as the larger one disperses the heat and light to a larger radius (reducing the spot effect). Also the 10" dome is deeper so less of the bulb sticks out to annoy the humans. I remember Meg showed a photo of the Mega Ray in a 8" dome and it didn't seem to work as well as the 10" I have and is also recommended by the manufacturer.

I didn't know I was supposed to have the bulb out of the enclosure for the burn in. I guess I am lucky that we didn't have any ill effects (didn't notice it as being any brighter). I will remember that when I replace it in June! The Mega Ray also undergoes slightly different testing than the T-Rex...I believe they may let it run a little longer to make sure it's not a dud.

Thanks Kate
I will definitly get the 10'' dome today, thanks for the clarification .

---

hah thanks. I read the instructions that came in the box. It was weird. My light was almost a shade of purple-ish blue when I first plugged it in. Pretty sure I tanned my retinas a little bit.

Same here, yesterday the light was a shade of purple-ish. Today, it looks better .

 

[nrfitchett4]

if you want to spend the money. zoomed makes a 10" deep dome mainly because of the large size of the mvb's. I am thinking of upgrading to one soon.

 

[Isa]

if you want to spend the money. zoomed makes a 10" deep dome mainly because of the large size of the mvb's. I am thinking of upgrading to one soon.

I went to home depot and they dont have the dome 10" so I went to the pet store and bought the exo terra one, it cost me 45$, it is a bit expensive if you want my opinion. Now I just dont know how I will put all the lights in the enclosure. Next weekend, my fiance and I will have to think about a way to put the 2*4 fuorescent llights and the MVB with the dome of 10" because there is only space for the 8" because it will touch the shop light. I will let the dome 8" until saturday, because I want to be there all day long to see if everything is ok with the temps and I am really scared of the fire, so I wont to be sure there are no danger.

 

[nrfitchett4]

why the need for all the lights? if you put the light/ heat and uvb together, the torts should migrate to it.
I buy most of my supplies from reptiledirect.com. Most pet stores (even petsmart and petco) usually charge double of what they do.

 

[tortoisenerd]

Wow $45 sounds expensive...mine was about $15 (Zoo Med?).

 

[Crazy1]

Kate where did you get a MVB for $15. The cheapest I have found is about $37. That was the T-Rex 100 watt.

 

[Isa]

why the need for all the lights? if you put the light/ heat and uvb together, the torts should migrate to it.
I buy most of my supplies from reptiledirect.com. Most pet stores (even petsmart and petco) usually charge double of what they do.

Hermy needs all the lights because he is a mediteranen tortoise and needs a lot of lights (that's what Danny told me and he is the specialist in Hermanns (and a lot of other species )

---

Wow $45 sounds expensive...mine was about $15 (Zoo Med?).

15$ for the 10'' ?? wow, where did you buy it from?
I bought mine in a pet store, the brand is exo terra.