Posted: Sat Apr 29, 2006 4:30 pm
Mercury vapor lights produce UVB, UVA and heat. Conventional UVB lights produce UVB, UVA, but an insignificant amount of heat (therefore an addtional heat source is necessary).
Probably the two most popular/well known mercury vapor lights are T-Rex's Active UVB Heat light and Zoo-Med's Powersun (but there are other brands as well). I've used and like the Active UVB Heat bulb, but have never tried the Powersun. I've read too many negative things about it, aminly with respect to it's longevity.
MVBs do not come in a tube style that I'm aware of. They can be either self-ballasted like the two mentioned or externally ballasted. Self-ballasted bulbs can be screwed into a regulalr socket, but because of the heat they generate, a fixture with a ceramic/porcelene socket is recommended. They should be hung vertically.
A MVB bulb would work well in a 124-gallon enclosure. If you get an Active UVB heat bulb, make sure it has a "milky" look to the bulb (i.e., not clear looking). The milky-looking ones are made with a newer technology that's better. Perhaps the older ones aren't being sold anymore, but it never hurts to check to make sure.
"You become responsible, forever, for what you have tamed." -Antoine de Saint Exupery-