UV sterilizer, algae scrubber plumbing

[BonelessEvil]

I'm planning on plumbing a UV sterilizer and algae scrubber together. The reason for this is that I have little room in my sump area to put the algae scrubber or the sterilizer. I'm going to run piping out of the sump, through the wall behind the tank and into the garage. There, I will run piping through the UV sterilizer and then into my algae scrubber, which will gravity flow water back through the wall and into the sump.

My question is which one should go first? Or does it matter? Should the water go through the algae scrubber and then fall through the UV sterilizer last? Or should it go the other way around. I'm thinking UV sterilizer, then algae scrubber. I only run the UV about a couple hours a day, just to cut down on free-floating algae. I need the algae scrubber, because I have a hair algae issue in my tank

 

[blaxsun]

I assume there's a pump in this scheme somewhere to force the water into the UV/algae scrubber in the first place? Gravity return is fine - just make sure you take the water post-sock filter and return it to a different chamber (such as the skimmer or directly into the return pump chamber).

 

[BonelessEvil]

I assume there's a pump in this scheme somewhere to force the water into the UV/algae scrubber in the first place? Gravity return is fine - just make sure you take the water post-sock filter and return it to a different chamber (such as the skimmer or directly into the return pump chamber).

I just wasn't sure if the UV sterilizer should go first (or the algae scrubber) in the chain or whether that matters.

 

[Turbo's Aquatics]

Usually the issue here is that a UV sterilizer needs a low flow rate for good contact time, otherwise it's not very effective.

Conversely, an Algae Scrubber needs a generally higher flow rate. Depending on yours, 15-30 GPH per inch of screen width is a general range. So if your scrubber is 6" wide, your flow should be minimum 90 GPH, preferrably more like 120 (20 GPH/in) and max 210 (35 GPH/in).

You might be able to balance these 2, but the flow is likely to be on the high end for the UV and the low end for the scrubber.

As for the order, if you pump to the scrubber first, then that has an air break so there is only gravity drain pressure (open drain) to go back through the UV - meaning you are trying to drain water out of the scrubber then into a small inlet, which is not likely to work well. You'll probably end up backing up the scrubber and overflowing it rather easily.

I would run through the UV first. If you have the room, split the feed line as you come out of the sump or through the wall and then you can use one feed with 2 different flow rates. Then I would route separate drain lines back to the sump. The UV should be pretty small as you won't need much flow (probably 1/2" vinyl hose) whereas the scrubber you will want to be larger because there's no pressure behind that after it comes out of the scrubber (same reason as above, you don't want to overly restrict an open drain)

HTH
Bud

 

[Turbo's Aquatics]

Good to know, thank you for sharing that! I'd be interested in reading the threads you refer to, and also would like to use them for future reference when helping others.

 

[Turbo's Aquatics]

copy/paste the URL, that's all you need to do