UV killing all beneficial bacteria?

[rob safron]

Want to hear some opinions. I have 125 gallon reef and for years have used vinegar dosing to keep nitrates at 1-3 and phosphates at 0.02 parts. Also have live rock and reactors with GFO, carbon, life Bio Fil rock. For years dosed 40 mls to vinegar to keep levels very low. Went through a bout of velvet that wiped out a lot of fish. Decided to add a UV from BRS and very happy with its performance and all old as well as new fish seem healthy, never a spot. However, several months ago my nitrates spiked around 25 and have been unable to get them any lower than 12-20. Tank looks OK, growing like weeds. I have vinegar currently at 110 mls and add bacterial every week, with UV and skimmer off. No movement on nitrates. Is it possible UV is the reason for the high nitrates? May try shutting it down for a while but curious if anyone has encountered the same thing.

 

[rob safron]

FYI, the UV reactor installed more than a year ago, not new.

 

[MSB123]

I find that when I remove my if, the water gets noticeably clouded.

 

[MSB123]

UV*

 

[rob safron]

Yep certainly keeps water clear. Once a week glass cleaning and it’s just starting to get covered lightly.

 

[Flippers4pups]

Most hobby grade UV units don't (without getting to technical) have enough power to do much in the way of parasite control. Effectiveness is dependent on dwell time with the water passing through it. They do little in controlling a parasite out break.

They will do well, if sized properly, clarifying the water collum making the water clear. Controlling algae blooms and bacterial blooms.

To the question of reducing anaerobic bacteria, anaerobic bacteria that reduces nitrates resides in dark low flow, low oxygen environments such as deep within rock, deep sand beds, etc.... A UV will not reduce their numbers.

 

[hart24601]

I have carbon dosed with UV and didn't have issues. You can take it offline for a week or two and see if anything changes. Most of the carbon dosing bacteria seemed to live in the sump for me as excessive carbon dosing made a slime in that area on carbon with its high surface area.

 

[rob safron]

This is what I assumed. Can’t figure out the sudden spike and why it won’t go back down with increased vinegar over about 4 months now.

 

[rob safron]

I am pulling the UV water from the sump where vinegar is dosed. I also noticed in the past if the vinegar dose is too high I would get a lot of white fluff all over the rock and don’t see that with high dose. Seems bacteria is not multiplying like prior.

 

[Denisk]

I personally don’t think uv is the reason for the high nitrates. They high nitrates are coming from waste. I’m not saying this is your issue but I noticed with my uv is that my algae is barely ever noticeable. Back when I didn’t run my uv, if I was over feeding my tank would show it. Now with a uv it’s very easy for me to overfeed and not see much algae. Unfortunately I can’t help with the vinigar dosing as I never did any kind of carbon dosing.

 

[Flippers4pups]

What's your P04?

 

[MSB123]

Most hobby grade UV units don't (without getting to technical) have enough power to do much in the way of parasite control. Effectiveness is dependent on dwell time with the water passing through it. They do little in controlling a parasite out break.

They will do well, if sized properly, clarifying the water collum making the water clear. Controlling algae blooms and bacterial blooms.

To the question of reducing anaerobic bacteria, anaerobic bacteria that reduces nitrates resides in dark low flow, low oxygen environments such as deep within rock, deep sand beds, etc.... A UV will not reduce their numbers.

I agree with “Hobby grade units ware not powerful enough to kill off parasites”
I have always run a commercially sized unit to kill off anything that in in the water cloud, and so I have to spot feed regurally. As an example, I run a 240 watt (3x 80 watt bulbs) UV sterilizer on my 200 gallon system and I have never had a problem with any disease. I run 2500 GPH through it (my return line) and I have never had any issues, as al of my water passes through it at least 200 times per day.

 

[rob safron]

What's your P04?

.02

 

[Flippers4pups]

What's your P04?

Never mind, I see it.

 

[OhDumb]

It could just be coincidence. You could have had a snail or hermit die without noticing.

 

[Flippers4pups]

Rob, you have heard "every tanks different" and that's true with bacteria as well.

I too have done what I could to reduce N03 in my system. Carbon dosing, chaetomorpha in a refugium, contemplating using a sulfur reactor.. .. etc.

My N03 levels stay around 40ppm currently. The thing is that my corals were paling recently. Goes against what we know, high nutrients =browning corals. Opposite was happening.

A friend here pointed me to my P04. He asked what it was. It was non detectable on my hannah checker. 0.00. he said dose some phosphate. I was phosphate limited.

Since I've stopped trying to lower N03 and been adding P04 for the past couple weeks and now my corals are coloring up and growing once again. I have no nuisance algae anywhere in my system.

What works for me, may not work for everyone, but it's been a huge improvement.

If your running around 10-20ppm N03 and as long as you have some detectable P04 AND your corals look good, leave it alone. Don't chase it.

 

[rob safron]

Yep. Corals are doing great. I am getting cyno which could be due to the vinegar or imbalance but all is pretty well. Pinks and reds are turning tan though.

 

[Flippers4pups]

Yep. Corals are doing great. I am getting cyno which could be due to the vinegar or imbalance but all is pretty well. Pinks and reds are turning tan though.

Cyanobacteria and dosing carbon go hand in hand. I'd stop dosing it.

On tan color, what's your alkalinity at?

 

[rob safron]

7.5

 

[Flippers4pups]

7.5

Okay, I should ask more about your system.

Sorry for all the questions, but it helps me understand what you have going on.

What's your water pramameters?
Tank equipment and can you post a picture of your tank?