UV Sterilizers: Are the benefits a MYTH or a REALITY?

[Kingston]

I am about 2 months into my first saltwater/reef tank (been doing African cichlids for 10yrs). I didn't get a UV sterilizer initially but when I started reading about my future fish choices esp tangs, it became clear to me that some were very prone to parasitic infections such as ich. I decided the cost of one or 2 fishes will pay for a UV sterilizer and hopefully decrease my risk of getting parasitic fish infection. So I just bought one but yet to plumb it in. I don't know if it will replace practices such as quarantine and premedication or rather a complimentary tool. I am yet to decide. There seem to be some science behind it.

 

[Charlie C]

UV will help but, as you suspect, it’s more of a complimentary tool. If set up correctly, it helps disease outbreaks to be less often and less severe. That will help generally healthy fish to fight off infections that have a life stage that freely circulates in your tank water. Good luck.

 

[jporter17]

Will a UV sterilizer kill beneficial bacteria from a sulfur denitrator? I have my UV plumbed into my return so 100% of the water being returned from the sump into the display is run through the UV sterilizer. Used to have it setup in the opposite where the water from the overflow fed through the UV into the sump. Wondering what would be the better configuration?

 

[Randy Holmes-Farley]

Will a UV sterilizer kill beneficial bacteria from a sulfur denitrator? I have my UV plumbed into my return so 100% of the water being returned from the sump into the display is run through the UV sterilizer. Used to have it setup in the opposite where the water from the overflow fed through the UV into the sump. Wondering what would be the better configuration?

When you say beneficial bacteria from a sulfur denitrator, what do you mean?

The bacteria doing the denitrating are attached to the sulfur in the denitrator.

Some will be washed out and perhaps become food for filter feeders, but a UV will not stop the denitrating.

 

[jporter17]

When you say beneficial bacteria from a sulfur denitrator, what do you mean?

The bacteria doing the denitrating are attached to the sulfur in the denitrator.

Some will be washed out and perhaps become food for filter feeders, but a UV will not stop the denitrating.

Yes, I didn't think that through. So all the nitrates will be consumed in the reactor and thus the reason for the effluent to read 0. I was somehow thinking that some of that bacteria would be flushed out of the reactor and was wondering if the UV would kill them on their ride to the display tank. Would it even matter if they were dead to alive to still have any beneficial value in the DT? Thanks for the expert advice. JP

 

[shafman1]

Running a pentair 40w on my 29 gallon and things have never looked better

I just added an 80 watt Pentair to my 540 gallon. I ended up hanging it on the wall. I had to leave enough space above it for bulb and/or quartz sleeve removal. I've been dealing with Cyano for quite sometime. I originally had an 18 watt Ultra V UV sterilizer from a previous 125 gallon tank. (It was supposed to be a 40 watt, but the bulb is 18) I disconnected it last year. The sleeve was broken on the Ultra V and it was way too small for my tank. The Pentair is pretty big, but it's working great so far. The algae and cyano are dying and clearing up fast. I have a dedicated Eheim 1262 (900 gph) on the Pentair. The water is crystal clear as well. ( less than a week). I was wondering why I had so much algae and cyano. I thought maybe there was more light hitting the tank glass in the warmer months. It slipped my mind that the UV was offline. I was going to try lanthanum chloride and maybe ferric oxide. Now I don't have to. I'm quite pleased the results.

 

[Randy Holmes-Farley]

I just added an 80 watt Pentair to my 540 gallon. I ended up hanging it on the wall. I had to leave enough space above it for bulb and/or quartz sleeve removal. I've been dealing with Cyano for quite sometime. I originally had an 18 watt Ultra V UV sterilizer from a previous 125 gallon tank. (It was supposed to be a 40 watt, but the bulb is 18) I disconnected it last year. The sleeve was broken on the Ultra V and it was way too small for my tank. The Pentair is pretty big, but it's working great so far. The algae and cyano are dying and clearing up fast. I have a dedicated Eheim 1262 (900 gph) on the Pentair. The water is crystal clear as well. ( less than a week). I was wondering why I had so much algae and cyano. I thought maybe there was more light hitting the tank glass in the warmer months. It slipped my mind that the UV was offline. I was going to try lanthanum chloride and maybe ferric oxide. Now I don't have to. I'm quite pleased the results.

What do you believe is the rationale for benthic algae to die when using a UV?

 

[Belgian Anthias]

I am about 2 months into my first saltwater/reef tank (been doing African cichlids for 10yrs). I didn't get a UV sterilizer initially but when I started reading about my future fish choices esp tangs, it became clear to me that some were very prone to parasitic infections such as ich. I decided the cost of one or 2 fishes will pay for a UV sterilizer and hopefully decrease my risk of getting parasitic fish infection. So I just bought one but yet to plumb it in. I don't know if it will replace practices such as quarantine and premedication or rather a complimentary tool. I am yet to decide. There seem to be some science behind it.

An UV lamp of sufficient strength will kill any parasites irradiated in the lamp but will have little impact on what happens in the aquarium in terms of breaking the life cycle of parasites present in the tank. An advantage is that parasite-free water can be obtained or, for example, when used after a skimmer, so that non-skimmable organisms cannot dominate.

 

[brandon429]

I think this thread speaks well to the power of collected anecdote patterning vs the trend to discount anything that isn’t peer reviewed and published

the vote for affirmation is overwhelming good above.

the sampled public is truly a valid source of info, free of charge all we have to do is sift for patterns, the tradeoff is attribution error for outcomes / am guilty on a daily basis of that/ but it doesn’t mean the overall data set is useless/ it’s pure free gold flecks among ore.


Responding to Randy’s post I truly have seen uv stop attached stringy hair algae in my 75 gallon planted tank. I suspect there are pelagic phases before or during benthic attachment phases and that intercept is the gold moment. I did dedicated hand removal before installing uv but not by scraping off the holdfasts, just by inputting a stick and twist rolling up the algae. With a giant over sized pond sterilizer rated for ten thousand gallons/ 4x tube array from grandmas pond/ the algae never came back. It was cheat burned away

I cannot count the number of reef tank wins we’ve cheated with installation of uv ranging from cyano to gha to dinos. More gaps are still needed to be filled for mechanisms but I’m sold and have been for 25 years on them. I have no idea how disease help works, if it was significant I’d expect Jay would add uv in the list of stickies. Currently that whole list is fallow and quarantine

 

[crezguy]

How to know if the UV light is working . I mean the results. Any easy way to find out like glass not getting the film for few days like that. How do we measure

 

[Gundy]

You need to target 336000uw/cm2 or higher to kill ich. There are studies showing it can take anywhere from 300k to 800k to kill ich in saltwater. Freshwater might be good in the 180-380 range. I usually take aquaUVs 90k flow rate and divide by 4.

I have heard these numbers as well. However I know most don’t run the flow through their UV’s slow enough to get that w36000 up/cm2 figure. What interesting is that they still are able to control parasites at probably 180000uw/cm2 or even less. It’s just difficult for many to purchase the correct unit(sometimes cost or space requirements) and then being able to run the flow slow enough. Perhaps the difference in flow (336000 to 180000)results in kill versus the parasites not being able to reproduce which would produce the same results. I’m just glad people are having success with controlling parasites within their tanks.

 

[jasonrusso]

I have heard these numbers as well. However I know most don’t run the flow through their UV’s slow enough to get that w36000 up/cm2 figure. What interesting is that they still are able to control parasites at probably 180000uw/cm2 or even less. It’s just difficult for many to purchase the correct unit(sometimes cost or space requirements) and then being able to run the flow slow enough. Perhaps the difference in flow (336000 to 180000)results in kill versus the parasites not being able to reproduce which would produce the same results. I’m just glad people are having success with controlling parasites within their tanks.

I don't believe that you can control parasites by only using a UV. The chances that all the water is going through the UV is not practical.

I have been Peroxide dosing the tank directly into my UV which supercharges the peroxide effect on parasites. I eliminated an active outbreak with peroxide.

 

[Belgian Anthias]

I have heard these numbers as well. However I know most don’t run the flow through their UV’s slow enough to get that w36000 up/cm2 figure. What interesting is that they still are able to control parasites at probably 180000uw/cm2 or even less. It’s just difficult for many to purchase the correct unit(sometimes cost or space requirements) and then being able to run the flow slow enough. Perhaps the difference in flow (336000 to 180000)results in kill versus the parasites not being able to reproduce which would produce the same results. I’m just glad people are having success with controlling parasites within their tanks.

Controlling? UV-C, if applied correctly, can render all pathogens in the treated water harmless at a sufficiently high dose. This is not the same as killing. By damaging DNA, they can no longer reproduce. In most cases, cells that have been damaged to that extent will also die, others are able to survive for a period of time. This in turn will become food for other organisms. As a result, organisms that have not been irradiated can develop more freely. And then the question is whether that is harmful or beneficial for the organisms for which we maintain the aquarium. Parasites and diseases have a life cycle that can be interrupted but also promoted in this way. I only recommend EV-c if a skimmer is used with the aim of sterilizing the skimmer's output water in order to neutralize the selectivity of the skimmer. This means that everything that comes out of the skimmer is rendered harmless, the dose used is high enough. The question remains, who or what benefits from it?

 

[Gundy]

I don't believe that you can control parasites by only using a UV. The chances that all the water is going through the UV is not practical.

I have been Peroxide dosing the tank directly into my UV which supercharges the peroxide effect on parasites. I eliminated an active outbreak with peroxide.

Interesting thought. How are you injecting peroxide directly into the UV? I have a 380 gallon tank that I will be setting up in the future. My plan is to run dual 120 watt UV’s on it through the 2 returns. Total overkill by at least 50 -75 percent but I think I could control an Ich outbreak. Here on R2R I have read numerous accounts of people controlling Ich with way smaller units but with proper flow. The disease is still present in the tank but just a lot lower numbers.

 

[jasonrusso]

Interesting thought. How are you injecting peroxide directly into the UV? I have a 380 gallon tank that I will be setting up in the future. My plan is to run dual 120 watt UV’s on it through the 2 returns. Total overkill by at least 50 -75 percent but I think I could control an Ich outbreak. Here on R2R I have read numerous accounts of people controlling Ich with way smaller units but with proper flow. The disease is still present in the tank but just a lot lower numbers.

I just run the dosing line directly into the intake of the pump. I put a plastic barb on the end and just wedge it into the grate on the pump. If you watch with a flashlight, you can see the peroxide (wavy looking water) going in.

I have a separate pump just for my UV. It's a 210g tank. I have 2 Eheim 1262 returns that are too fast for any sort of UV dwell time. I wanted to have control of the UV flow so I installed a DC pump.

 

[Gundy]

I just run the dosing line directly into the intake of the pump. I put a plastic barb on the end and just wedge it into the grate on the pump. If you watch with a flashlight, you can see the peroxide (wavy looking water) going in.

I have a separate pump just for my UV. It's a 210g tank. I have 2 Eheim 1262 returns that are too fast for any sort of UV dwell time. I wanted to have control of the UV flow so I installed a DC pump.

I assume you use a dosing pump to deliver the peroxide. How much do you dose and is it constant for what period of time? Is this your idea or do you have any other info available For a detailed technique?

 

[jasonrusso]

I assume you use a dosing pump to deliver the peroxide. How much do you dose and is it constant for what period of time? Is this your idea or do you have any other info available For a detailed technique?

My twist on this thread. I'm also dosing a much larger concentration because it's fish only. My reef tank gets a lower dose. The 2am to 9am dosing is the most important.

How To - Peroxide (H2O2) dosing for parasites in reef tank

***Current dosing recommendation for active outbreaks, using 3% hydrogen peroxide*** (a TLDR for people who just need to know how to get started) Week 1: 1mL/8g, 3x per day Week 2: 1mL/5g, 3x per day Week 3: 1mL/5g, 3x per day, plus overnight dosing. Continue the week 3 dosing regimen for a...

humble.fish

 

[Azael]

I think it’s very useful. I bought it a few months back when my fishes had ich and it helped a lot. No casualties.

 

[Gill the 3rd]

I think it’s very useful. I bought it a few months back when my fishes had ich and it helped a lot. No casualties.

I had the exact same experience. I don't run it all the time, but when I see my fish have ich, I run my UV and it definitely helps.

 

[Nano_Man]

Yep they maybe help a bit with algae and free swimming cycle of disease but I don’t run them in my book survival of the fittest and natural immune systems in the fish works out in the natural sea environment