It's almost as cheep to take the light to a good pet shop and buy a new light, that size. think petco petsmart etc
A very good place specialising in fish may carry the part you need, more than likely a mom & pop place.
A hardware store is only as good as the floor person you happen to get, some don't know as much as they think they do.Take the whole lamp, you never know just what information you might have left at home.
The bulbs they sell at pet stores are the ones you want, Hardware stores usually do not sell the best bulbs for aquariums. It's a matter of what wavelengths of light are given off. A bulb that you can read a book by isn't quite as good as what's required for the fishes best health.
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Ol' Paint, 88 Base coupe auto.
Turning white on top, like owner.
Leaks a little, like owner.
Doesn't smoke....... OK, we're trying to quit.
[This message has been edited by DtheC (edited 08-25-2009).]