Ballasts and Wattages

[Stu :)]

Hiya,
Couldn't find the answers here anywhere handy and the local electrical shop wasn't much help... I was wondering can you use a bigger/greater wattage value ballast to drive smaller/less wattage light tube/s? For example use a 39/40W ballast to drive a 24W tube.

I have a twin output 45W electronic ballast lying around and the (rhymes with smittity) Chinese 24W ballast driving two 24W T5s in my 120L planted tank has packed a sad. If all else fails I can buy a new one with same wattage for less then $20NZ and a wander down the road.

Stu

 

[Clay]

I *believe* the ballasts for HOT5s are just over driving bulbs. Typically, the answer is yes, you can (within reason), and the result is a shorter life bulb.

I think the 40w ballast may be overkill on the 24w bulb, but try it out and see!