UV Use: Unless Your Using it for Parasite Control are They More Beneficial or Detrimental?

[livinlifeinBKK]

Ok, first off I'm not trying to knock anyone who uses a UV. I know there are plenty of successful tanks that use UVs but personally I've always been wary of them due to the fact that they kill the free swimming bacteria that can be beneficial and have heard they can drop ORP as well which is something to take into consideration when using them for algae control...is this a valid concern? Curious what Randy and @Timfish thinks about it...

 

[blaxsun]

I have a (reasonably) successful tank with a UV. I haven't had any algae issues (zero), disease outbreaks and the water is crystal clear. My ORP ranges from 390-430 during the day, so I'd say that UVs lowering ORP levels is a myth.

I'm sure others have varying opinions, but for me running without a UV isn't an option.

 

[livinlifeinBKK]

I have a (reasonably) successful tank with a UV. I haven't had any algae issues (zero), disease outbreaks and the water is crystal clear. My ORP ranges from 390-430 during the day, so I'd say that UVs lowering ORP levels is a myth.

I'm sure others have varying opinions, but for me running without a UV isn't an option.

Yeah, like I said there are plenty of successful tanks out there with UV...as for the water quality is concerned my tanks are crystal clear with just using carbon so I don't have a reason to run a UV personally... I'm primarily just curious what everyone has to say

 

[JGT]

Same as ^^^. Also the majority of bacteria are on the surfaces within the tank, ie rock, sand, sump, etc. so I think the UV effect on bacteria is minimal.

 

[livinlifeinBKK]

@Randy Holmes-Farley what do you think? I know the nitrifying bacteria live on surfaces but some other beneficial bacterial strains live in the water column. Also I have no idea if the ORP decrease is true or not...

 

[blaxsun]

Also I have no idea if the ORP decrease is true or not...

I just told you it's not. I could post a graph, but I guess if you need confirmation from others...

 

[livinlifeinBKK]

I just told you it's not.

Sorry, read your post too fast!

 

[taricha]

I know there are plenty of successful tanks that use UVs but personally I've always been wary of them due to the fact that they kill the free swimming bacteria that can be beneficial and have heard they can drop ORP as well which is something to take into consideration when using them for algae control...is this a valid concern?

removing "beneficial" planktonic bacteria...
- using that logic we wouldn't run skimmers
- many planktonic bacteria can multiply faster than the turnover for slow UV.
- if you sequenced them and looked at the families you might not feel like they were "beneficial" anyway.
- killing bacteria in the water is more likely to just displace that activity to more surfaces rather than prevent that activity from happening.

ORP....
- there are many more plausible mechanisms for UV raising ORP than lowering it.
- ORP wouldn't be a good indicator on algae growth anyway.

Those are my thoughts. I don't think either argument is a logical reason to avoid UV.

 

[Randy Holmes-Farley]

I personally did not use a UV.

In typical use I don't think its a big deal, but my rationale was that I dosed vinegar to boost bacteria as a filter feeding method, and I did not want to grow them just to kill them again in a UV.

A UV acting on organics in the presence of O2 should generally raise ORP, but if you kill a lot of bacteria and they spill their low ORP internal contents, that might possibly lower ORP. That said, I do not consider ORP to be something to target.

 

[livinlifeinBKK]

I personally did not use a UV.

In typical use I don't think its a big deal, but my rationale was that I dosed vinegar to boost bacteria as a filter feeding method, and I did not want to grow them just to kill them again in a UV.

A UV acting on organics in the presence of O2 should generally raise ORP, but if you kill a lot of bacteria and they spill their low ORP internal contents, that might possibly lower ORP. That said, I do not consider ORP to be something to target.

Thank you Randy. I'm not personally for or against UV use I was just curious as to what insight people may have to share...I'm doing the same as you using carbon dosing to boost bacterioplankton populations so it would be counter productive for me. I've just been learning a lot about the microbiome and have learned that although nitrifying bacteria along with many others grow on surfaces there are in fact plenty of bacterial strains in the water as well...just trying to further my knowledge

 

[flashsmith]

I use a UV on all 3 of my systems. Never had algae issues other than cleaning glass as needed. Never any parasites and I don't quarantine ever. Corals thrive and numbers are stable with just bi weekly water changes and dosing a couple times a week. Then again I don't lose sleep over numbers and I'm no scientist. There's all kinds of ways to find success in a reef tank. From a visual I definitely know when it's time to service the UVs just by the way the water looks. Some people don't believe in water changes. Some people quarantine everything. Both are successful and both have had epic fails. There's no right or wrong way in my opinion. It can't hurt to use them. If I ever get to the point of micro management in my tanks it's time to find a new hobby.

 

[Jon's Reef]

Recently moved to a bigger tank. Cycling over the last few months. Livestock transfer over the last few weeks. Just moved the UV over on May 4.

Anecdotally went from cleaning glass daily/ every other day to once per week.

 

[doubleshot00]

I look at it as there is no harm in using one so why not.

 

[hart24601]

UV can be an absolute miracle worker for combating dinos, depending on the species. Ime dinos are quite sensitive to UV and it doesn’t take much to kill them. I had to keep uv on my tank constantly to combat them - as have 3 other local reefers. Elevated nutrients are present, the uv seems to be the only thing that holds them in check. I have wondered if we in the hobby didn’t bring in a new strain(s) in the past few years as I never had issues before but that’s another conversation. If I remove UV the coral will start getting killed in under a week.

 

[livinlifeinBKK]

UVs sound pretty good after hearing all this! The only reason I don't use one is because I like to have the bacterioplankton in the food web since they play such an essential part in the cycling of nutrients on natural reefs. I just prefer to control nutrients that way and plus it gives my corals extra nutrition. As someone said before there are many ways to run a successful tank. I thought it might be an interesting topic to start and learn from what everyone else is doing.

 

[Randy Holmes-Farley]

I use a UV on all 3 of my systems. Never had algae issues other than cleaning glass as needed. Never any parasites and I don't quarantine ever. Corals thrive and numbers are stable with just bi weekly water changes and dosing a couple times a week. Then again I don't lose sleep over numbers and I'm no scientist. There's all kinds of ways to find success in a reef tank. From a visual I definitely know when it's time to service the UVs just by the way the water looks. Some people don't believe in water changes. Some people quarantine everything. Both are successful and both have had epic fails. There's no right or wrong way in my opinion. It can't hurt to use them. If I ever get to the point of micro management in my tanks it's time to find a new hobby.

What do you see in the water when it’s time to change bulbs?

 

[schooncw]

Following.

 

[iMi]

It's a common misconception that UV lights kill "free flowing" beneficial bacterial. Nitrifying bacteria lives on the surfaces of rocks, deep in the sand bed, etc.

UV sterilizers damage the DNA of free flowing organisms, like parasites, certain algae, dinoflagellates and other pest.The key is flow. You must expose the organism for the right amount of time and reputable UV light sellers will specify flow rate for parasites and single cell organisms. They are very effective and I wouldn't go without one anymore.

 

[livinlifeinBKK]

It's a common misconception that UV lights kill "free flowing" beneficial bacterial. Nitrifying bacteria lives on the surfaces of rocks, deep in the sand bed, etc.

UV sterilizers damage the DNA of free flowing organisms, like parasites, certain algae, dinoflagellates and other pest.The key is flow. You must expose the organism for the right amount of time and reputable UV light sellers will specify flow rate for parasites and single cell organisms. They are very effective and I wouldn't go without one anymore.

No, UV doesn't differentiate between bacterial strains...it kills whatever bacterial pass through it. You're correct in saying that most of the nitrifying bacteria live on surfaces but there are many bacteria that live in the water column which UV sterilizers kill. These are the bacterioplankton that corals capture and use for a portion of their nutritional requirements.

 

[Lowell Lemon]

No, UV doesn't differentiate between bacterial strains...it kills whatever bacterial pass through it. You're correct in saying that most of the nitrifying bacteria live on surfaces but there are many bacteria that live in the water column which UV sterilizers kill. These are the bacterioplankton that corals capture and use for a portion of their nutritional requirements.

They use the plankton dead or alive so what is the reason to avoid UV? Many of the viruses in sea water actually attack the bacteria causing them to spill their contents into the water column where filter feeders and corals capture the products as food source.

I have visited a R2R members tank in Bangkok that utilized UV to great effect in his system. I think the thread is titled Reef on the 10th floor. Amazing and beautiful tank!