Ballast rating vs lamp rating

[DaftPunk]

I've got a UV filter for my pond which takes a 55W 1200mm lamp. Unfortunately the ballast has burnt out and failed shorted to earth.

Ballasts for 1500mm 58W tubes are readily available and cheap. Will the additional 3W rating cause an issue or do I need to try and source a 55W ballast?

 

[ericmark]

With a wire wound ballast I have found although they may work when the voltage or wattage is not correct when you measure the power used they either take more or less than the design current and the tube life is reduced.

With a HF electronic ballast there is often a range rather than a single wattage and with these lamp life is longer. One 18W lamp at the top of my stairs lasted nearly 20 years before I had to change tube which was second hand to start with.

As to UV tubes I know with some special ballasts are used I would be wary of using the wrong one.