UV sterilizer.... Is it worth it to run?

[Delphinus]

My opinion is a solid "it depends."

Here's my take on it. If nothing else, UV will break down the organic compounds in the water that tend to cause the water to get that yellow tinge to it, and then this can be skimmed out. So if nothing else, a UV *can* polish the water up some. The water will have a noticeably brighter or clearer look to it.

To actually have UV act as an anti pathogenic tool you need a fairly large unit. I have one myself, think it's a 57w unit, that I keep onhand in case I ever get a bad ich outbreak. When I ran it in the past it did help keep it at bay (not a silver bullet, but it did make a difference with fish that had really bad ich and they were able to overcome it in the end). Anything 20w or less is probably not going to work for this although it will still help polish the water.

Like anything however there are pros and cons. For example, the glass tube the light sits in will need regular cleaning (some units have a built in wiper but not all). Like any light, the UV lamp itself will lose intensity and will need replacing. If you run it 24/7 you will probably need to replace it as soon as 6 months. Maybe longer if you don't run it 24/7 but if you're going for the anti pathogen effect I would imagine you need it on 24/7.

HTH