Over Sized UV

[m.kristoff]

I am building a 155 mixed Reef. I am a big fan of UV
I have a 57watt Aqua UV. Its over sized and my issue is how much flow is really necessary for it to be effective?
Recommended Flow Rate for Saltwater Applications:

Saltwater Reef Applications: 2133 GPH - 3200 GPH

Protozoa Bacteria Water Flow Rate: 1066 (min), 3200 GPH (max)

I am beginning to think that this way over sized to be effective, or is it??

I have a L2 return pump but since relocating my sump, i am considering getting a core 20 for the return

My plan was to run the UV off of a manifold

options
1. drop down to a 40watt
2. get a core 15 to run the UV on its own. (Estimated flow 1450 gph)
3. keep the 57 watt and run at reduced flow (estimated 1500GPH)
4. use the L2 and run it off of a manifold (L2 3100GPH)

I will have an estimated 12' of head pressure

 

[Quietman]

No such thing as oversized UV! I overstate of course.

For tanks under about 300 gallons it's reasonably economical to get one UV unit at a constant flow rate to manage both algae (low exposure/8x tank turnover) and protozoan (high exposure).

You'll need 8x true tank turnover (certain organisms - dinos for example - have a fast reproduction rate of double in about 20 min - the 8x true tank turnover is needed to keep up). 8x 155 gallons is 1240 gph. So that falls into the range for your 57 watt for protozoa and you can cover both types of organisms at one flow rate.

By the way - make sure 8x is true tank turnover and not flow rate. Usually either piping direct return line or a closed loop dedicated for UV is required.

Good Luck!

 

[blaxsun]

What brand of UV do you have? My AquaUv 57-watt indicates a max of around 1100 Gph for parasites.

 

[Quietman]

And yes, with my math as @blaxsun hinted at, you are a bit underpowered for all protozoa. But (and this is my opinion) correcting an outbreak is different that ongoing management and these things are expensive. So getting an 80 watt might be ideal but I think you'll be fine at 57 w since you already have it and it should provide enough.

In my experience the flow I need to correct issues is less than what I need to keep them managed.

 

[m.kristoff]

My

What brand of UV do you have? My AquaUv 57-watt indicates a max of around 1100 Gph for parasites.

I have an AquaUV as well. Got the info form BRS website and i believe they got that from AquaUV

 

[m.kristoff]

So my takeaway is flow and running it inline to be most effective. I was planning on running off of a manifold and recirculate it in the sump. I have done that in the past but i believe opinion s about UV has changed over the years since I have been out of the hobby

 

[blaxsun]

I have an AquaUV as well. Got the info form BRS website and i believe they got that from AquaUV

It's a really good UV and not that difficult to mount (try to install it with the barbs facing up if you can). I run mine @45% (~565 Gph) which is about 2.85x turnover, but I can increase this to @85% (~1,065 Gph) in a pinch. I prefer the higher "stun" dwell time for additional UV exposure.

I'm running a separate pump for the UV, diverting about ~75% of post-filtered water through it into the skimmer chamber. I'm running stock plumbing without a manifold so I had limited options available.

Prior to this I had an outbreak of velvet, and between the new UV and medication I haven't had any incidents in over 4 months (and I've probably added more than a dozen fish during this time).

 

[m.kristoff]

Spoke to BRS and AquaUV this morning and of course got conflicting information

BRS claims I don't need to run between 2100-3100 gph to kill algae
AquaUV claims I do need to run it that fast because it's a 57watt. they also said that i should not run it slower for pest control as it effects beneficial- not sure I buy that since it's for a 300+ gallon system. I'm running a 155


I get Tank volume + flow (turn over) + wattage
My tank is a 155

AquaUV 25 watt is rated for 150 gallon

Saltwater Reef Applications: 800 GPH - 1200 GPH
Protozoa Bacteria Water Flow Rate: 400 (min), 1200 GPH (max)

AquaUV 40 Watt rated for 325 gallons

Saltwater Reef Applications: 1930 GPH - 2900 GPH
Protozoa Bacteria Water Flow Rate: 967 (min), 2900 GPH (max)

AquaUV 57 watt rated for 355 gallons

Saltwater Reef Applications: 2133 GPH - 3200 GPH
Protozoa Bacteria Water Flow Rate: 1066 (min), 3200 GPH (max)

Since my tank is a 155, I believe that my flow rate falls between the 25 and the 40-watt specs for Protozoa Bacteria and Reef applications

I was thinking that I would run it to stop algae during the day and slow it down for Protozoa/ Bacteria at night.

I believe that my nighttime flow to be effective should be between 600 and 900 GPH

Any suggestions of what my daytime rate should be?

 

[m.kristoff]

part of of BRS conversation. they say that slow rates sterilize everything. Ick, algae, bacteria and diatoms???

 

[costaricareef]

2. get a core 15 to run the UV on its own. (Estimated flow 1450 gph)

I don't think you'll get close to that with 12 feet of head. I have a bout 4 real feet plus the elbows, maybe 6-8 feet equivalent with the 1.25"coupling, reducing to 1" and then out on 1/2" sea swirl and 3/4" loc-jet. I get maximum 650gph with my COR15 at 100%. With the head table I seem to remember it was around 800ggh at 10', so not so bad.

 

[m.kristoff]

I don't think you'll get close to that with 12 feet of head. I have a bout 4 real feet plus the elbows, maybe 6-8 feet equivalent with the 1.25"coupling, reducing to 1" and then out on 1/2" sea swirl and 3/4" loc-jet. I get maximum 650gph with my COR15 at 100%. With the head table I seem to remember it was around 800ggh at 10', so not so bad.

I changed it up. I now have 2 COR 20's. Thinking that I would run 1 for manifold that would have the UV on it and the other one for the return. also gives me a backup if the main goes down

 

[VermontReefs]

It's a really good UV and not that difficult to mount (try to install it with the barbs facing up if you can). I run mine @45% (~565 Gph) which is about 2.85x turnover, but I can increase this to @85% (~1,065 Gph) in a pinch. I prefer the higher "stun" dwell time for additional UV exposure.

I'm running a separate pump for the UV, diverting about ~75% of post-filtered water through it into the skimmer chamber. I'm running stock plumbing without a manifold so I had limited options available.

Prior to this I had an outbreak of velvet, and between the new UV and medication I haven't had any incidents in over 4 months (and I've probably added more than a dozen fish during this time).

What type of pump are you running with your 57w Aqua UV?