Thoughts on Aqua UV Hang on Light?

AlexVic · Oct 30, 2025

The space between my sump and Aquarium is really small so I’m finding it really hard to find a regular UV sterilizer. Is the aqua uv hang on light good? How would it work if I’m using 2 return pumps now, would I need to decrease the speed of the original return pump? Also should I run the sterilizer 24/7 or just 12 hours a day? Any advice would be greatly appreciated!

FUNGI · Oct 30, 2025

IMO...you are better off just getting a cheap small pump and throwing it into your sump to power this....and just HOB the unit to your sump
no plumbing hassles

AlexVic · Oct 30, 2025

FUNGI said:
IMO...you are better off just getting a cheap small pump and throwing it into your sump to power this....and just HOB the unit to your sump
no plumbing hassles

So I should put the pump in front of the mechanical filtration and have the sterilizer exit the water in the return chamber?

FUNGI · Oct 30, 2025

doesn't really matter.....even in the return area would work. What this kills will bypass any filtration anyway

AlexVic · Oct 30, 2025

FUNGI said:
doesn't really matter.....even in the return area would work. What this kills will bypass any filtration anyway

Thanks for the help

mcarroll · Oct 30, 2025

AlexVic said:
Any advice would be greatly appreciated!

Why are you installing it? That will dictate how it should be installed.

AquaUV has a document that tells you what flow rates you need to target.

In a nutshell: If it's for algae, it almost doesn't matter how it's installed – algae is easy to treat.

If it's for parasites, UV dosage matters, so it should be installed for maximum effectiveness, including the actual flow rate through it, following AquaUV's guidelines. No water from the filter section/sump should bypass the UV if it's for parasites, if you're trying to be serious. Consider also running micron filtration if parasite control is the mission. They make a good combination.