The Planted Tank Forum banner

How long do UV Sterilizers take to work? Green Water Takeover!

19248 Views 8 Replies 6 Participants Last post by  Kip
After reading through all the threads on GW, I picked up a UV sterilizer yesterady. It's been running for over 24 hours and I can't notice any difference ... water still green with 6" visibility! :mad:

Does anyone know how long these take to kick in?

BTW, my eheim canister pump died last week and it took 3 days for the replacement part to get it going again, hence the GW outbreak.

Thanks for any replies!
1 - 9 of 9 Posts
What wattage UV. After I did a major (50% for three days) it took about about four days to notice the difference. I use a 18w with my Eheim pro.
Depends on how you have it connected (power head, canister, etc.)? The slower the water going through the UV, the better.

If you have a 6 watt UV and connecting it through a powerhead/pump/canister, with a GPH of 250, then the water is going through fast.

What model UV?
It's some cheap Chinese one from the LFS ... same one as here ... 9 watts at 200 gph.

Owner of LFS (smart guy) said it would be enough even though I have a 250. Now I'm thinking I should get another. :icon_roll
The cheap 9w AA UV sterilizer from took about a week to clear my 65gl, but the GW was clearing a tad after a few weeks of growth when I added the UV, so I'm still not sure if it did it alone. I'm not sure what the gph is of the attached powerhead, but this thing is slow as molasses, when it emmersed during a water change, the water was dribbling out of it.
it depends on a few factors.
-how bad the situation is in the tank.
-how effective the UV design is.
-how much flow can the UV unit handle effectively and how much turnover is really occurring.
well 48 hours and a 50% wc later the GW is about half gone. can actually see my tv through the tank now! :icon_roll
Whoo! I used a diatom filter for my GW. Small tank though...couldn't see more than an inch into the tank. I actually used a ruler to see. =p

Diatom filter cleared it up in about an hour (again, small tank) once I got it setup all correctly. Dumb me left a gap where all the GW flowed through without becoming filtered. Oops!
Four days later quite good ... 5 days later and crystal clear!
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.