Sizing a UV for Reef Tank - Any truth in this ?

[Kmsutows]

I completely agree, no one really knows and keeping an open mind is important but we also know that “ old reefers tales” are believed....my response was a sarcastic one in response to Kmsutows answer suggesting his tank was proof that they worked..

My comment as also sarcastic because asking for "proof" is silly. At the same time, as anyone knows, Achilles are more prone than just about any fish out there to get ich so putting one in a known ich tank and it not getting the parasite is about as good as it gets. Again, they wouldn't use them commercially if they didnt work.

 

[Mortie31]

My comment as also sarcastic because asking for "proof" is silly. At the same time, as anyone knows, Achilles are more prone than just about any fish out there to get ich so putting one in a known ich tank and it not getting the parasite is about as good as it gets. Again, they wouldn't use them commercially if they didnt work.

What I don’t get is that as others have said there are no scientific papers on UV’s eradicating Ich, and other parasites, which leads me to question why not?

 

[ca1ore]

What I don’t get is that as others have said there are no scientific papers on UV’s eradicating Ich, and other parasites, which leads me to question why not?

Somebody's got to be willing to fund it; and it is a quite specialized use case. Absent sufficient sample size, and all other variables fixed, the anecdotal things people report are meaningless.

 

[Mortie31]

Somebody's got to be willing to fund it; and it is a quite specialized use case. Absent sufficient sample size, and all other variables fixed, the anecdotal things people report are meaningless.

Exactly and the manufacturers don’t need to bother doing it either, if people believe the anecdotal reports and buy them

 

[ca1ore]

Haha, well, you're assuming a proper scientific experiment would conclude that UV is not effective against parasites. If it concluded that UV is effective, then they'd sell more ......... As it is, anecdotal reports go both ways. Not a lot of folks use UV on their tanks these days so it might actually be in the manufacturers interest to fund a study.

 

[Mortie31]

Haha, well, you're assuming a proper scientific experiment would conclude that UV is not effective against parasites. If it concluded that UV is effective, then they'd sell more ......... As it is, anecdotal reports go both ways. Not a lot of folks use UV on their tanks these days so it might actually be in the manufacturers interest to fund a study.

Actually quite the opposite, i would love them to be proven to work, they would be a good relatively cheap control method, as I previously said I use UV on both of my koi ponds and even my little goldfish and Orphe ponds, as they are proven to kill floating algae... I just have a bee in my bonnet about the huge anecdotal support so many products get on these forums

 

[Steve Fast]

I suspect the real market is aquaculture and less so the importers, public aquaria, and aquatics stores. As for sizing, that likely has already been worked out by the manufacturers so they can provide guidance to their customers. For grins I was thinking about approaching a trade group or the government agency in charge of supporting aquaculture research (USDA?) to see if anyone is interested in funding it. Modeling could be done with a few grad students and wet lab work a few more. Gotta find a wet lab collaborator....

 

[Kmsutows]

Hopefully this attachment works... showing it includes ich... I don't understand why it is so hard for people to grasp. It's a very simple concept and used in commercial industry.. they would not invest so much in it if it didnt work.

 

[Lowell Lemon]

Should have included more info, I run Dual Suntail Reeflo pumps, they each runaround 4000 gph, I will run 1 reeflo at 4000 gph through the UV. The total water volume in the system is 850 gallons so that's about 5 times turn over an hour of total tank volume through the UV...... My issue is they are saying I should NOT size it higher than 45,000μw/cm² flow rate for a Reef Tank. If that's the case, I will not be able to kill any type of ich. And a few things I have read, the Florida Study, and also other companies data concerning ich flow kill rate suggest I should be running a kill rate 2 or 3 times the 90,000 μw/cm².

Thanks for any help on this sizing problem on the new UV.

One of the texts I read recently mentioned 100,000 micro seconds per cubic meter of flow to kill C.I. If this is true then you would need a higher dose than the 45,000 or 90,000 being recommended. That said however in most cases the advantage is to keep levels below pathogenic concentrations. So in this case you are getting the advantage of limiting populations at levels that would be a problem to the host fish. Their natural immunity should take care of the rest provided you give excellent nutrition and keep the water quality very high in order to reduce stress on the fish. I used 45,000 with great success in central filtered marine systems for retail pet stores.

 

[Randyp79]

The other thing to consider is that the UV dose doesn't necessarily have to be lethal to be beneficial. I wish I could find it, but I once read a study that talked about how even sub-lethal doses of UV radiation could have a negative impact on Cryptcaryon's ability to divide and reproduce successfully. Essentially, the UV damaged the DNA enough that proper replication and reproduction didn't occur.

One of the texts I read recently mentioned 100,000 micro seconds per cubic meter of flow to kill C.I. If this is true then you would need a higher dose than the 45,000 or 90,000 being recommended. That said however in most cases the advantage is to keep levels below pathogenic concentrations. So in this case you are getting the advantage of limiting populations at levels that would be a problem to the host fish. Their natural immunity should take care of the rest provided you give excellent nutrition and keep the water quality very high in order to reduce stress on the fish. I used 45,000 with great success in central filtered marine systems for retail pet stores.

 

[Lowell Lemon]

The other thing to consider is that the UV dose doesn't necessarily have to be lethal to be beneficial. I wish I could find it, but I once read a study that talked about how even sub-lethal doses of UV radiation could have a negative impact on Cryptcaryon's ability to divide and reproduce successfully. Essentially, the UV damaged the DNA enough that proper replication and reproduction didn't occur.

I agree and that sticks in my mind from previous study on the subject.

 

[Lowell Lemon]

What I don’t get is that as others have said there are no scientific papers on UV’s eradicating Ich, and other parasites, which leads me to question why not?

By the way there are studies including the one I just read today. I am of for the next three days but Google effects of U.V. on C.l. and I.M. and see the science. It works quite well actually. I designed holding systems for my customers (aquarium stores) and the had very positive results. It is even mentioned as a solution for large scale outbreaks in aquaculture.

 

[Mortie31]

Hopefully this attachment works... showing it includes ich... I don't understand why it is so hard for people to grasp. It's a very simple concept and used in commercial industry.. they would not invest so much in it if it didnt work.

It’s so hard to grasp... because as I said in one of my first posts, if you go higher and higher with the uv exposure you will kill ich, but you will also kill every water born organism in your tank, I personally don’t want that... it’s about the balance.. if I wanted to kill everything in my water good and bad, there are lots of chemicals available as well as uv, but that’s not a good idea either, there are obviously several differing view points on here and experiences, which is good.. simply showing uv exposure charts isn’t proving anything, I need to know what else it kills and will there be a detrimental effect on my tank... hence we don’t use copper in a reef tank

 

[Steve Fast]

It works for two reasons:

1. flow rate through UV has sufficient kill the target.
2. the UV is destroying the target faster than it can reproduce.

If the target is causing more harm to your system than the benefit from any collaterally damaged beneficial organisms, I'd use it. Once the target is gone, turn off the UV, and we could repopulate the beneficial organisms. If the target is out of control, the natural balance is out of whack. So you have to reset the natural balance by whatever means.

 

[Mortie31]

It works for two reasons:

1. flow rate through UV has sufficient kill the target.
2. the UV is destroying the target faster than it can reproduce.

If the target is causing more harm to your system than the benefit from any collaterally damaged beneficial organisms, I'd use it. Once the target is gone, turn off the UV, and we could repopulate the beneficial organisms. If the target is out of control, the natural balance is out of whack. So you have to reset the natural balance by whatever means.

I know and understand the mechanics of how they work... however the scenario you point out here is possibly why people think Uv’s are vital and become dependent on them, if a system is balanced, biologically and chemically, not over stocked, doesn’t have inappropriate fish, has sufficient filtration and doesn’t have all of it’s diverse biological life messed around with, by UV’s and chemicals, a lot of these problems wouldn’t arise, or the system is more able to deal with them itself, the very fact of altering the biology of a system can induce stress into the system which can exacerbate whitespot etc, hence you increase your demand for quick fixes like uv’s... but then again I may be unique in my way of thinking...

 

[Steve Fast]

I know and understand the mechanics of how they work... however the scenario you point out here is possibly why people think Uv’s are vital and become dependent on them, if a system is balanced, biologically and chemically, not over stocked, doesn’t have inappropriate fish, has sufficient filtration and doesn’t have all of it’s diverse biological life messed around with, by UV’s and chemicals, a lot of these problems wouldn’t arise, or the system is more able to deal with them itself, the very fact of altering the biology of a system can induce stress into the system which can exacerbate whitespot etc, hence you increase your demand for quick fixes like uv’s... but then again I may be unique in my way of thinking...

I agree. I prefer the holistic approach. Just sometimes despite our best intentions and practices, the system gets out of balance. When that happens we need to address it using one of the appropriate means. UV is one as well as the others you have mentioned.

 

[14 foot reef]

I went through the same exercise about 6 weeks ago. Seems like we've both found the same U Florida extension article (http://edis.ifas.ufl.edu/fa164) which gives an industry standard of 280,000 µWsec/cm2. So I set my flow to dose UV at 360,000 µWsec/cm2. Then I purchased sufficient UV power ( in my case 2 units at 150 watts each) to turn 99.9% of the tank over in 4 hours according to Hamza's calculator (https://www.hamzasreef.com/Contents/Calculators/PumpTurnover.php). This means that, assuming uniform distribution of the pathogen (reasonable enough given the internal flow in the tank), the buggers have much less than 4 hours to find a host. This knocked the ich out in my tank after the existing parasites had fallen off their hosts in ~ 4 days. No signs since then which has been over 4 weeks... Was very rewarding to see the fish liven up and swarm for food once again...

Hope this helps....

What is your flow rate?
What units did you choose ?

 

[Steve Fast]

What is your flow rate?
What units did you choose ?

Two of the E150S. I run them at 500 gph roughly doubling the power on the target. Specs are found here https://smhttp-ssl-29106.nexcesscdn.net/media/docs/general-SmartUV-Line-UV.pdf. Also got a flow switch for each so they would auto shut off if the flow is off. These are found at https://pentairaes.com/flow-switches.html

Oddly the price is up from when I bought them a month ago...

 

[Land Shark]

UV is about reducing the numbers of algae spores, pathogens and pests in a closed system to smaller, more manageable numbers. Water clarity is improved quickly and fish have a better opportunity to build up immunities over time. Get the proper sized UV that fits in your budget and within the space you have to work with. You will have fewer fish losses over time and you can bank on it!

 

[Jet915]

UV is about reducing the numbers of algae spores, pathogens and pests in a closed system to smaller, more manageable numbers. Water clarity is improved quickly and fish have a better opportunity to build up immunities over time. Get the proper sized UV that fits in your budget and within the space you have to work with. You will have fewer fish losses over time and you can bank on it!

This. It helps water clarity and since I implemented it I havent lost any fish to parasites. I researched it and got an oversized UV (Pentair 40 watt) for my 100 gallon. I have it running at 210 gph which supposedly is sufficient to kill ich. This along with selcon in their diet and stable water seem to do the trick so far. It does heat your water pretty good though.