Habitat - Indoor :: MVB Bulb

[SpotsMama]

Here's another way to put it. My 100 watt MVB flood produces an 88 degree temperature at 16". I wouldn't even try to measure it at 6" because I think it would break the thermometer. It would cook the turtle.

[N4784N R4613]

Something's wrong here. The mercury vapor bulbs - even the lowest wattage floods - are extremely intense. I can attest that they get very hot. It would be dangerous to put one of those bulbs closer than 12" to an animal. It has to be a typo in the T-rex website.

Here's some advice from a site called UV Guide UK, An Introduction to Mercury Vapour Lamps:

Manufacturers always state a minimum safe basking distance; for many lamps it is 12" or 18" from the face of the lamp. Closer than this, your reptile may receive dangerously high levels of UV radiation.

It's also adviseable to keep your lamp directly above the basking spot - overhead, like the sun. The shape of a reptile's head and position of the eyes ensures that overhead light will not cause it to suffer from the glare.

A mercury vapour lamp which needs to be placed a minimum of 12" directly above a basking spot, just won't fit inside most small set-ups - there isn't enough headroom. However, if the vivarium has a wire mesh or screen top, the lamp can be hung outside the viv, at a suitable distance above the mesh, and the beam directed down to a basking spot below. Bear in mind, though, that wire meshes and screens will block a percentage of the UV light, as shown in our mesh test results. (Glass or plastic sheets will completely block the rays and thus cannot be used.)

Always check basking temperatures right underneath a mercury vapour lamp.

Yes, there was a typo. I happen to own one(100 watt spot) it works great! I just so happen to have the box it came in and here is a pic of the side panel...



You can't really see it, but it saids...

100 watt flood – 12”

100 watt spot – 18”

160 watt flood – 18”

160 watt spot – 36”

275 watt flood – 24”

[steve]

The info on that website is 5 years old. The package was printed in 2005. I believe Marisa mentioned that they came out with "improved" technology, so it's possible that website is seriously outdated.

[N4784N R4613]

I got a quick question that I didn't want to start a new topic for. My water heater is set at 76F, but when I turn on my MVB the water temp goes up to 77.5F and stays there all day until I turn it off. Then it drops back down to 76F. Is that ok?

[Kallistos]

I edited, I've become accustomed to trusting everything that's on a company's website, I thought a company as large as T-rex would keep their information updated! Well, in that case, I'm not sure how far I would be able to elevate the bulb, I'll find out, maybe go with the 100 watt, i'm not sure.

Nathen, I doubt that a 1.5 degree fluxuation will affect your turtle negatively, but that's just my guess...

[SpotsMama]

Looks good!

[steve]

N4784N, that is fine. Just make sure that the basking area is about 10F warmer than the water.

RESowner34, it's not your fault. I'm also surprised that they have such an outdated site. I go crazy if I don't redesign a site after 12 months. (... and this site design is over 12 months old )

[N4784N R4613]

One more question. Does any one know if I can use a dimmer on a MVB? Or does it need "full power" to operate properly?

[steve]

I don't have a definitive answer, but I haven't seen dimmers with MVB or halogens. It's a definite no to fluorescents. So I'm guessing no in general. Also, the MVB is very sensitive - sometimes it goes out by itself and you can't turn it off and back on right away... you have to wait about 10 minutes.

[Kallistos]

I'm just curious, would a 100 watt flood provide enought UVB from about 18" away even if it has to go through a 1/2" screen mesh? I heard that if you put it any closer that the reptile could get UV poisoning, which to me seems like the MVB gives off a lot of UVB. I'm not terribly considered wether it will light up the whole tank, just if it'll provide enought UVB. So basically 18" away throught 1/2" mesh...

[steve]

This should give you an idea about the UVB output:

http://www.carolinapetsupply.com/uvb_ou ... _bulbs.htm

[Kallistos]

How many microwatts/cm² do Red Ear Sliders need. Also, how many microwatts/cm² does a 1/2" mesh filter out?

[steve]

Not sure, but you can see that they are getting way more than what fluorescents provide.

[SpotsMama]

In nature the turtles get the full blast of UVB rays from the sun. I think the sun is the "gold standard" of UVB sources. Anything less than that should be ok for your turtle.

[steve]

In nature the turtles get the full blast of UVB rays from the sun. I think the sun is the "gold standard" of UVB sources. Anything less than that should be ok for your turtle.

Absolutely! One thing to consider, the full blast of Sun only peaks around noon. A MVB might be on for 8-10 hours a day, so it is possible for a RES to get too much UVB.