UV flow rate for Ick

Steven9194

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I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.
 

winxp_man

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For best results, it’s good to tie it into the return side of the sump. I have to look at what I have mine setup up at flow wise.

Remember it only helps so much. And good QT practice is still a good thing to practice.
 
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Steven9194

Steven9194

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For best results, it’s good to tie it into the return side of the sump. I have to look at what I have mine setup up at flow wise.

Remember it only helps so much. And good QT practice is still a good thing to practice.
I was told to set it up directly into the DT when I used it for dinos last year.

Currently have ick in the tank and I’m trying to get by a few more days until I can get the QT all setup. Then I’ll be removing the fish and running fallow.

Just looking for some help with what flow I should have my UV setup at in the meantime.
 

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I don’t understand why tying it into the return chamber is best? You want to recirculate the display? I have my 80W plumbed into one of my displays closed loops.
Full water contact that is going back into your tank. In the DT it only cycles so much still can’t cycle all contaminated water. Plus most modern systems having massive pipes over the tank edge is a ghetto look if you ask me. So to get this straight, I have line tied into my rerun line going back into my tank.

I run mine off the main return line. After a few days dinos were completely eliminated. I can let my tank roll for two weeks before I have to scrub my glass.
 

UncommonSense

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however I cannot find the correct flow rate for Ick management
Assuming you have this “classic” model,


here’s this UV’s minimum allowable flow rate; at or near this mark will give you maximum possible exposure time to any waterborne parasites!

IMG_8510.png
 

WhatCouldGoWrong71

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Full water contact that is going back into your tank. In the DT it only cycles so much still can’t cycle all contaminated water. Plus most modern systems having massive pipes over the tank edge is a ghetto look if you ask me. So to get this straight, I have line tied into my rerun line going back into my tank.

I run mine off the main return line. After a few days dinos were completely eliminated. I can let my tank roll for two weeks before I have to scrub my glass.
My UV can’t be seen (back left corner of this video, tank was under construction). This tank has been wet 10 months now and I think I have had the UV on maybe 36 hours. I look at UVs as kind of a last resort. But yeah, I clean my glass about every 2-3 days.

 

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I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.

I don't know the exact answer for that particular model, but I do know that for a 40W Pentair the flow rate for Marine Ich is 120 gals per hour.

It' needs to be very slow in order to achieve at least 280,000 uW/cm exposure. Any faster and ich will not be sterilised
 

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Full water contact that is going back into your tank. In the DT it only cycles so much still can’t cycle all contaminated water. Plus most modern systems having massive pipes over the tank edge is a ghetto look if you ask me. So to get this straight, I have line tied into my rerun line going back into my tank.

I run mine off the main return line. After a few days dinos were completely eliminated. I can let my tank roll for two weeks before I have to scrub my glass.
My UV can’t be seen (back left corner of this video, tank was under construction). This tank has been wet 10 months now and I think I have had the UV on maybe 36 hours. I look at UVs as kind of a last resort. But yeah, I clean my glass about every 2-3 days.

OT butAdding extruded rails under the sump is genius. Been reefing way to long to not have seen /thought of that. Thank you.
 

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I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.
You want slow rate for effectivity an I dont use return but rather its own pump
 

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I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.
So, for Ich with a 57W Aqua UV:

  • Aim for around 1,000-1,300 GPH if possible. That gives a more usable UV dose for parasite control.
  • If you want even more assurance and can afford to slow it further (and you don’t need a high turnover), going down toward **~ 1,000 GPH or less** will improve the contact time.
  • Make sure the lamp is new or well-maintained (clean quartz sleeve), as performance drops with lamp age/dirt.
I would aim for the 1000gph to 1200gph

Source: https://edis.ifas.ufl.edu/pdffiles/FA/FA16400.pdf

According to the MFG, a flow rate of 1,066 GPH for your model would be required in order to achieve 90,000 μw/cm2: https://www.aquaultraviolet.com/dru...tions-Classic-and-Twist-Series-06-25-2015.pdf
 

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So, for Ich with a 57W Aqua UV:

  • Aim for around 1,000-1,300 GPH if possible. That gives a more usable UV dose for parasite control.
  • If you want even more assurance and can afford to slow it further (and you don’t need a high turnover), going down toward **~ 1,000 GPH or less** will improve the contact time.
  • Make sure the lamp is new or well-maintained (clean quartz sleeve), as performance drops with lamp age/dirt.
I would aim for the 1000gph to 1200gph

Source: https://edis.ifas.ufl.edu/pdffiles/FA/FA16400.pdf

According to the MFG, a flow rate of 1,066 GPH for your model would be required in order to achieve 90,000 μw/cm2: https://www.aquaultraviolet.com/dru...tions-Classic-and-Twist-Series-06-25-2015.pdf

90,000 uw/cm2 is nowhere near enough for marine ich, that number is for freshwater ich.

As i said above you require in excess of 280,000 uW/cm for marine Ich.

Any manufacturer who states 90,000 is incorrect/misleading.
 

Amstar

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Correct - the calc was for freshwater for saltwater ich for that uv (my mistake)

To hit 180,000–280,000 µW·s/cm² for saltwater ich, you’d need to cut flow roughly in half (or more) than the freshwater calculation above in my previous post
  • ~500–600 GPH → ~180,000 µW·s/cm² ( for marine ich prevention).
  • ~350–400 GPH → approaches ~280,000 µW·s/cm² (therapeutic range for outbreaks)
 

SeaWhatYouSave

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You’re going to hear a lot of conflicting advice on UV sterilizers. The truth is, there haven’t been any scientific studies comparing different UV sterilizer setups in a hobby aquarium environment, so we’re all making educated guesses based on intuition and experience.

Most published studies focus on the question: “If ich passes through a UV sterilizer once, what dose of UV light is required to kill it?” That’s not really applicable to an aquarium, because water continuously recirculates through the sterilizer. If the flow rate is too fast to kill ich in a single pass, it can still be effective: parasites are weakened with each exposure, and higher flow means more of them are exposed to the UV. Even a half-lethal dose of UV seriously damages ich.

In fact, I’d argue it’s worse to run a sterilizer too slow than too fast. Once the lethal dose is reached, extra exposure doesn’t add benefit--you’re just wasting light that could be treating more water. In my opinion, wattage is the key metric for UV sterilizers, not flow rate. Higher-wattage units produce more intense UV light, killing more organisms overall. Always get the biggest unit you can fit in your setup; for example, I run a 55-watt sterilizer on my 60-gallon system.

As for placement, I believe the best possible setup is a closed loop directly on the display tank: a pump pulls water from the display, runs it through the sterilizer, then returns it to the display. This directly treats the water your fish live in. If that’s too cumbersome or unattractive, the next best option is putting the sterilizer in your return line (return pump -> UV -> display). What I wouldn’t recommend is a sump-to-sump loop, because sterilizing sump water doesn’t benefit your fish.

Lastly, I want to stress that UV sterilizers won’t stop a severe ich outbreak. If multiple fish are already sick, there is no sterilizer that you can buy that will save the tank on its own. UV is best used for prevention and for controlling bacterial/algal blooms, not as a cure for outbreaks! I've found that the best management strategy for controlling parasite outbreaks in a display is actually to lower the tank's temperature, because that slows the rate that the parasites grow and reproduce. I run my tanks at 75-76 degrees and have found that it slows the rate of spread of ich and velvet significantly compared to 78+.
 

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I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.
For parasite control, UV only helps against diseases that have a free living theront stage - ich or velvet. Then, the applied dose needs to be on the order of 200,000 us/cm2. This is about double the power of your unit. Plus there is the fact that the ich theronts emerge from the tomont cysts in the early morning and attach to the fish at the bottom of the tank - never going through the UV itself.

These units serve a purpose for limiting free floating algae (green water issues). They can also help reduce the spread of disease when water is dosed from one tank to the next in a series (like a commercial system). Otherwise, I feel that the cost/benefit just isn't there for most hobbyist sized units.
 

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I run one of these using a 1" supply and my cor 20 pump only gets 530 gph according to the flow meter in line. Im probably cooking the **** out of everything. I was hoping to get closer to the 2k GPH. i may replumb to get closer.

According to the website :

Recommended Flow Rate for UV Dosages at 30,000 µw/cm2 (EOL) GPH: 3,200 (Max Flow Rate)
at 45,000 µw/cm2 (EOL) GPH: 2,133
at 60,000 µw/cm2 (EOL) GPH: 1,600
at 75,000 µw/cm2 (EOL) GPH: 1,280
at 90,000 µw/cm2 (EOL) GPH: 1,066 (Min Flow Rate)

Information for Reef Tanks
A UV rated in the 30,000 or 45,000 µw/cm2 (EOL) is ideal for the reef environment. UV’s used at higher kill rates will destroy the planktonic food supply for the reef.

Information for Marine Fish (No reef or live rock)
A UV rated in the 75,000 or 90,000 µw/cm2 (EOL) will be the most effective at controlling fish disease.

All UV dosages are calculated at the end of lamp life (14 months).

Based off this you want 2133- 3200 gph for reef and 1066-1280 to kill fish diseases.
 

Jay Hemdal

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I run one of these using a 1" supply and my cor 20 pump only gets 530 gph according to the flow meter in line. Im probably cooking the **** out of everything. I was hoping to get closer to the 2k GPH. i may replumb to get closer.

According to the website :

Recommended Flow Rate for UV Dosages at 30,000 µw/cm2 (EOL) GPH: 3,200 (Max Flow Rate)
at 45,000 µw/cm2 (EOL) GPH: 2,133
at 60,000 µw/cm2 (EOL) GPH: 1,600
at 75,000 µw/cm2 (EOL) GPH: 1,280
at 90,000 µw/cm2 (EOL) GPH: 1,066 (Min Flow Rate)

Information for Reef Tanks
A UV rated in the 30,000 or 45,000 µw/cm2 (EOL) is ideal for the reef environment. UV’s used at higher kill rates will destroy the planktonic food supply for the reef.

Information for Marine Fish (No reef or live rock)
A UV rated in the 75,000 or 90,000 µw/cm2 (EOL) will be the most effective at controlling fish disease.

All UV dosages are calculated at the end of lamp life (14 months).

Based off this you want 2133- 3200 gph for reef and 1066-1280 to kill fish diseases.

The trouble is that Cryptocaryon tomites/theronts require 180,000 to 200,000 µw/cm2 for anything close to an effective kill. To get that, you need to reduce the flow rate to nil. That in turn allows for the parasite to reproduce enough to carry on the infection.

Here is a good resource from Roy Yanong:


Use of ultraviolet (UV) sterilization to kill theronts has been suggested, based on research involving Ichthyophthirius multifiliis (freshwater "ich"). The recommended UV dose for Ichthyophthirius theronts is 100,000 µWsec/cm2 (Hoffman 1974). However, UV doses required for Cryptocaryon irritans are anecdotal or extrapolated, and range from 280,000 µWsec/cm2 (industry numbers) to 800,000 µWsec/cm2 (Colorni and Burgess 1997).

Theronts must go through the UV sterilization unit in order to be exposed, so any theronts that are not exposed to UV radiation and remain in the tank or holding areas will be unaffected. Similarly, encysted tomonts within the tank or holding area will not be affected.


Jay
 

mcarroll

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Agreed so far.

I have a 57w Aqua UV setup on my 125g aquarium, however I cannot find the correct flow rate for Ick management. If someone could please help me out I would really appreciate it.

I have it setup in the DT and not the sump, if that makes a difference.
You are making an implicit assumption (in the title at least) about targeting only ich. (Actually Cryptocaryon)

If that's really your case, then you want micron filtration....the thing that makes Crypto "hard to hit" with UV is what makes it "extra susceptible" to micron filterin – it's huge. That means that it doesn't even take a very specialized filter, almost any micron filter will work...most are under 50-100µ, but some like the Marineland around 25µ. Any of those should help....and there's little need to go smaller than 25 µ, but it's possible if you had a reason to.

DT is going to be the most effective....and if it's going to be a temporary install, that's probably the best overall way to have it.

If installed in the sump, as AquaUV says in their manual, you would not want any sump water to bypass the UV/micron section. 100% sterilization is the goal for parasites.
 

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