Why does my UltraKlean Pond Filter still have green water? April 18, 2026 02:37 UV must be set to 24-hour operation during algae bloomsFlow must be slow enough for UV exposureBulb must be within service life Related articles What should I do if my UltraKlean Pond Filter is not working effectively? Why is the UV light not turning on in my UltraKlean Pond Filter? How to Take Care of Slightly Green Water Why is my UltraKlean Pond Filter returning dirty water? Why is my UltraKlean Pond Filter backwash valve hard to turn or not working?