# Same ballast - smaller bulb?



## Mr Fishies (Sep 21, 2007)

I have an older Hagen Glo ballast kit that is intended for 2x 30W (36") fluorescents, is there any reason it can't be used with 2x 20W (24") bulbs?

I know overdriving is adding a second ballast to a set of lights, but what about just using an oversized ballast? I'm not trying to get more light, just trying to re-purpose.


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## ameekplec. (May 1, 2008)

I assume by using 24" bulbs in a 36" fixture, you're going to DIY a new fixture?

I'd have to imagine that the bulbs will have a reduced life.


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## Harry Muscle (Mar 21, 2007)

All depends on the ballast. Some of the better and more expensive ones have a range of bulbs that they can drive but chances are yours is designed for 30W bulbs ... meaning if you redo things and run a 20W bulb you you'll probably be overdriving things ... meaning risk of fire and everything else that comes along with overdriving a bulb. It's all a matter of if you wanna risk it or not ... it's most likely not designed to be used that way unless you happen to have one of those special ballasts that is (it'll say usually on the ballast what it's designed to power).

Harry


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## Mr Fishies (Sep 21, 2007)

Thanks for the warning - that's just what I was worried about.

I'm just not sure how it works with fluorescents and ballasts. I wasn't sure the ballast would deliver 30W to the bulb regardless, or if the ballast was designed to support *up to* 30W and something smaller wouldn't be an issue since it was drawing less power (kind of like replacing a 100w incandescent with a 40w incandescent...was hoping it would just use less power and fit over a smaller tank).


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