We use a UV clarifier in our indoor hydroponic system, and have even used one in our aquaponic system a time or two.
In the aquaponic system we mostly used the clarifier to sterilize water on startup. At the beginning of an aquaponic systems’ life there can be algal blooms and all kinds of weirdness. Once the system evens out, this is less of an issue.
We also use clarifiers in our hydroponic system, where they help with controlling algae in the system. You usually won’t use it long term but it’s good to have in case algae flares up or you have problems with bacteria.
A UV clarifier is usually a plastic or steel cylinder with a lamp housed inside. In that lamp is a filament that produces UV light. This light sterilizes the water flowing around it, which prevents algae build up. It’s a simple and easy way to build something into your system that will take care of bacteria and algae on the front end.
We’ve worked with several different types of UV clarifiers over the years and have never had trouble. They are typically easy to plumb in and come with clear instructions on doing so.
You will have to replace the shroud pretty often. Since the shroud is quartz (glass filters UV), they can be pricey, so be careful not to break them!
To stay energy-efficient, size the lamp to your system (size it to the volume of water that you’re moving) well.
UV clarifiers are a great tool to have in your toolbox to control the biology of your water. They are especially useful in controlling algae for both hydroponic and aquaponic applications.