Need Question ABout Mercury Vapor Bulb Answered

[Mina]

Disclaimer, currently it's 2:44am so please excuse typos/oddly worded things.

My name is Mina and i just joined this community a few minutes ago because I really cant seem to find an answer to this question i've been trying to figure out and I do know it's quite silly and may sound dumb however bare with me, I'm new.

I'm planning on buying a bearie of my own sometime in Feburary of next year. For the past month or two, every single day i've beeen researching bearded dragons to prepare me. I've come to the conclustion that I want to use a mercury vapor bulb as they give off the best UVB. However, my issue is what other lighting i use with it. From my understanding,(correct me if im wrong) in a norma lenclosure you would need a basking light, a normal household bulb, and a ubv/uva lighting. Also from my understanding, a mercury vapor blub gives off uvb/uva and heat and a basking spot and that would be the only light needed. To sum it up, the question is as follows:

Is a mercury vapor bulb all in one and the only light i will need for a 40 gallon breeder for a baby bearded dragon?

Thank you <3

PS: If this question is dumb, it's not my fault researching beardies is confusing!

 

[PatsyB]

As far as I know the answer is yes, the MVB covers both your UVB and your basking needs. Just keep in mind that UVB should cover 2/3 of the tank and an MVB concentrates your UVB to just one area of the tank. I know lots of people use MVB and they are okay with it but most people use separate bulbs. Another thing to keep in mind is cost. Since your MVB is both your UVB and basking, if the bulb blows out, you need to spend another $60 to replace it. Where if you have separate bulbs, if your basking bulb blows, you only have to replace that and not your UVB. You can use just a normal halogen flood lamp that you can get at the hardware store for a few bucks.

 

[Efvie]

Most of the mercury vapor bulbs I am seeing on Amazon are only $30, not $60. The most expensive one I saw in a quick survey was $50.

 

[BeardedHippy]

Hi, since questions about MVB bulbs seem to crop up a lot I regularly go see what new info is out there about them. While they sound ideal as an all in one solution, there are things you should take into consideration. MVBs are designed for use with large, well ventilated vivariums (4-5ft across), they are not dimmable so can't be used with a thermostat. In a small vivarium they can easily overheat.
While they may produce a lot of UV they deteriorate quickly, around 70% over its lifespan, the majority of which happens in the first 3 days of use and then levels off. It is reccomended that UV tube lighting is still used in conjuction. Their lifespan is an average of 6 months, though they can last as little as 3 months (type and make of bulb may be a factor here), a cheap one may die on you pretty quickly. This is because they are filament lamps, they are delicate and dont like vibration or movement (electrical things vibrate).
As Patsy pointed out, if the bulb blows, you lose light, heat and UV. If you use MVBs, you should always have a spare on hand just in case.
The lack of control and short lifespan puts me off them, but if you can get past that they are quite efficient.

(There is a myth that they produce UVC, but it is not true. UVC is is at the bad end of the UV spectrum)