Do you have green water?
If you just have algae attached to surfaces in your tank a uv
sterilizer won't help with that.
You should look at why you have algae rather than trying to just combat it with a uv
sterilizer. Also, you'll be looking at a UV
clarifier, not a sterilizer. It all works in relation to dwell time, so given that you'll be using it as a clarifier I'm not sure you'll have enough dwell time for the beneficial bacteria to be killed. What is the wattage and how many gph
is flowing through?
If you're trying to just use it as a powerhead though...just buy a powerhead. If you're trying to use it as a clarifier, make sure you have green water rather than just algae forming. If it isn't free floating algae spores then the clarifier isn't going to do anything as it will only effect the water that passes through it. Look at your lighting, plants, fertilizers, and make sure it's not just a bacteria bloom.
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