The Great UV Debate... I don’t care

[Whip]

Out of curiosity why is this. What’s the difference if your running on display vs sump. All the same water that’s moving through both. I’ve be contemplating one for a while and have a area where my sump is that I could add one.

I believe it is all about efficiency (introduction of unsterilized water to UV) and duration (time exposed to UV). Duration is solved by flow rate. Admittedly, running my UV off of my header is slightly inefficient as there does exist a chance that a percentage of my Just sterilized water will get sterilized again... and at the sake of some unsterilized water.

 

[JReef85]

I believe it is all about efficiency (introduction of unsterilized water to UV) and duration (time exposed to UV). Duration is solved by flow rate. Admittedly, running my UV off of my header is slightly inefficient as there does exist a chance that a percentage of my Just sterilized water will get sterilized again... and at the sake of some unsterilized water.

Ok. That makes sense if plumbed that way. Let’s say tho I run a separate pump just for the uv. If I pull water right after the roller mat and then exit near my return pump in theory I wouldn’t be re sterilizing any of the same water. That should be as efficient as having it run of the display?

 

[Whip]

Here is my set up and why it is slightly inefficient...

Four water molecules fall down from the DT into my overflow chamber. They go through my filter media and into the big refugium area. They eventually drop into the return chamber and get sucked up by the return pump. At this point in time, they get split. Two go up to the DT and two go the the sterilizer. The two that went to the DT, fall back into the overflow chamber where they meet their now sterilized buddies. They all lock arms and go through the filter media, through the refugium, and into the return chamber. Again, they all get sucked up by the return pump, but this time one sterilized molecule and in unsterilized molecule go to the sterilizer and the same goes through to the DT.

That story would make a good bedtime story for my kids!

Anyway, regardless of how efficient or inefficient it is, it seems to work (see original post).

 

[jaxteller007]

I had the same concerns. I watched BRS install it on a header, then watched them call that a mistake. I have mine installed on a header. It works (see original post).

I went to my build thread to snag a photo, but didn’t have an one that was updated. Here is a photo snapped from this morning. I didn’t get to clean my sump, but you can tell it stays pretty clean.

LOL at didn't get to clean your sump. Thats cleaner than my display honestly lol.

 

[Gregg @ ADP]

I stopped using UV sterilizers on reefs 15 years ago, and haven’t thought about them since

 

[jaxteller007]

I stopped using UV sterilizers on reefs 15 years ago, and haven’t thought about them since

We know we have ich in our system and have mostly tangs so it concerned us. Plus I basically got it for half price.

 

[JReef85]

Makes sense

 

[Futuretotm]

Here is my set up and why it is slightly inefficient...

Four water molecules fall down from the DT into my overflow chamber. They go through my filter media and into the big refugium area. They eventually drop into the return chamber and get sucked up by the return pump. At this point in time, they get split. Two go up to the DT and two go the the sterilizer. The two that went to the DT, fall back into the overflow chamber where they meet their now sterilized buddies. They all lock arms and go through the filter media, through the refugium, and into the return chamber. Again, they all get sucked up by the return pump, but this time one sterilized molecule and in unsterilized molecule go to the sterilizer and the same goes through to the DT.

That story would make a good bedtime story for my kids!

Anyway, regardless of how efficient or inefficient it is, it seems to work (see original post).

your example Only works if you have 50% of water from your return going through to your DT and 50% to your UV, which is unlikely if you’ve setup slower flow through your UV for sterilization of algae vs parasites.

Likely 10 h2o come down
8 return to DT and 2 get zapped in the UV
20% of the 2 = 0.4 get re zapped
And the cycle goes on

Mathematically the DT vs Sump UV debate doesn’t make sense to me. Perhaps someone who knows what they’re talking about comes along.

 

[Whip]

your example Only works if you have 50% of water from your return going through to your DT and 50% to your UV, which is unlikely if you’ve setup slower flow through your UV for sterilization of algae vs parasites.

Likely 10 h2o come down
8 return to DT and 2 get zapped in the UV
20% of the 2 = 0.4 get re zapped
And the cycle goes on

Mathematically the DT vs Sump UV debate doesn’t make sense to me. Perhaps someone who knows what they’re talking about comes along.

Yup. Very true. My simplified version doesn’t take into account that the two water molecules that went to the DT likely take a long time to go down the overflow again. All the while, the sterilized ones have a greater probability to be sterilized again and again.

I’m not a mathematician and this is definitely a statistics and probability problem. All I know is that anecdotal evidence leads me to think UV makes a difference AND the way I have it plumbed in (efficient or not) adds value.

 

[Gregg @ ADP]

We know we have ich in our system and have mostly tangs so it concerned us. Plus I basically got it for half price.

I have ich in every single system I do, along with pretty much everything else

 

[jaxteller007]

We have a separate pump in our skimmer section pulling water to the UV and it exists into our return section.

 

[Jet915]

We have a separate pump in our skimmer section pulling water to the UV and it exists into our return section.

Same here, separate pump where u can dial down the flow.

 

[benapilot]

Resurrecting an old thread....

I'm thinking about putting one on my 150 gallon mixed reef. No Tangs or sensitive fish yet, but they're on the horizon. I'm looking at the Octopus Varios Pumps to feed my UV. It's got the 0-10v Apex control built in. Would it benefit to run 12 hours at low flow, and 12 hours at high flow?

 

[Whip]

Resurrecting an old thread....

I'm thinking about putting one on my 150 gallon mixed reef. No Tangs or sensitive fish yet, but they're on the horizon. I'm looking at the Octopus Varios Pumps to feed my UV. It's got the 0-10v Apex control built in. Would it benefit to run 12 hours at low flow, and 12 hours at high flow?

Someone actually asked this in a BRS Q&A session about UV. I believe the answer was yes, you can do it as long as you understand that you will reduce the effectiveness of both types of objectives; by how much is a complex math problem.