Could'nt sleep last night had a idea in my little head

[Viking]

HID bulbs for marine aquarium use are feasible, provided you do it properly. Sticking a headlight above your tank with a cheap hid bulb in it, and expecting it to work isn't the way to do it.

See here for how it should be done. Link.

I've run a HID kit in my works van for over 3 years, driving for approx 4 hours per day. I always drive with my headlights on, and I've never had a bulb (or ballast) fail on me yet. Newer cars run HID (xenon) direct out of the factory (as does my car) and again driven with headlights on all the time. Up to 80k miles on it now and still original bulbs.

[yorky1]

I have read about people using Xenon and HID bulbs which gave good results when the higher K rating bulbs were used. But they only lasted a couple of weeks or months at best before blowing. Despite the fact the on cars they probably last years they are not being hung vertically with all the heat generated going back into the housing and electrical contacts which they are not designed for, i believe this is the cause of the shortened life of the bulbs.

eddy

[Viking]

Which is why I said it has to be done properly. They do not generate an awful lot of heat, much less than a standard headlight bulb in fact, but if housed in a projector then the heat is not a problem.