Persistent Nitrite Problem Despite 5 Months, No ammonia Low Nitrates

[LuigiScReef98]

Hi everyone,
I’m having trouble with persistent nitrites in my small reef tank and could really use some advice from more experienced reefers.

Tank setup:

• 50 L reef tank (running for about 5 months)
• Started with ~5 kg of CaribSea South Seas synthetic rock and ~1 cm layer of live sand
• Using RO/DI water (4-stage)
• Gradually added livestock over the last month (as soon as i succeded to get ALMOST 0 nitrites):
  • 1 Amphiprion ocellaris
  • 1 Gramma loreto
  • 1 Lysmata amboinensis
  • 2 Trochus snails
  • Soft corals: Zoanthus, Sarcophyton, Pachyclavularia, Litophyton
  • LPS corals: Euphyllia paradivisa, E. glabrescens, Caulastrea, Rhodactis

Current water parameters:

• Ammonia (NH₃): ~0.05 mg/L [JBL]
• Nitrite (NO₂): 0.05 – 0.35 mg/L [Tropic Marin]
• Nitrate (NO₃): around 1 mg/L or less [Tropic Marin]
• pH: stable, around 8.1
• Temperature: 24-25°C

The tank looks stable otherwise, but nitrite has never dropped completely in 5 months. I’ll attach a chart showing my water test results over time: since about 2 months I reached the minimum testable ammonia value. You can see some "cycle iterations" from the chart, specially for nitrites. Now i have stable low nitrates (1ppm) and roller coasting nitrites.

I forgot to mention that I used bacteria (nitrifying + denitrifying) + carbon sources as protocol from my local store. After added the livestocks I had to perform consistent water changes (30-40% during some of the no2 spikes). Any advice on how to help nitrite finally drop to zero — without disrupting the system or stressing the corals — would be really appreciated.

Thanks in advance!

 

[Miami Reef]

I don’t believe the results are real.

In any case, nitrite is not toxic at all in seawater. I actually almost never recommend testing it because it’s an insignificant parameter.

It is toxic in freshwater tanks though.

 

[LuigiScReef98]

Thanks for your answer.

Meanwhile I also found https://www.reefkeeping.com/issues/2005-06/rhf/index.php, confirming what you said. Unfortunately there's so much misinformation by product sellers. Instead this article is so well documented. Thanks again, I'm more quiet about my fishes now.

I don’t believe the results are real.

Out of curiosity, why you don't think results are not real? They are not "realistic" in some kind of sense?

 

[Miami Reef]

Out of curiosity, why you don't think results are not real? They are not "realistic" in some kind of sense?

Nitrification bacteria grows predictably. It doesn’t make sense that a population didn’t establish after adding live snail shells, coral skeletons, bottled bacteria, and live sand.

 

[BryanM]

Out of curiosity, why you don't think results are not real? They are not "realistic" in some kind of sense?

The presence of nitrites, especially in that .3 range, SHOULD produce false high nitrate testing results..... That is why I am questioning these results.

You should also test phosphates.

 

[LuigiScReef98]

Hi, I also Have a Lysmata Amboinensis. NO2 is now at 2ppm. Will it tolerate this value or should I do a WC?

I cannot understand why my tank no2 are not stable yet, 5 months now cycling it. Also because ammonia stabilized to 0 from months. I hope all will go ok for my animals…

 

[Randy Holmes-Farley Verified Community Expert]

There is no evidence that nitrite is toxic to any organisms at any levels ever attained in any reef tank.

I’d suggest stopping testing of it.

 

[dvgyfresh]

I am having the same “issue”, can’t for the life of me figure it out , I also started with all live rock. However , yesterday I actually fixed the water level in my tank to make the baffles actually do something in the AIO lol so maybe it was due to food rotting in the back chambers - world wide corals has a video on reef nutrients

 

[LuigiScReef98]

Reasoning about my clearly not done cycling: I read about incomplete denitrification phenomena, in which nitrates do not convert completely to nitrogen and the process stops to nitrate. The bacteria prod I used contains both nitrifying and denitrifying bacteria. Is that possible?

 

[mcarroll]

Thanks for your answer.

Meanwhile I also found https://www.reefkeeping.com/issues/2005-06/rhf/index.php, confirming what you said. Unfortunately there's so much misinformation by product sellers. Instead this article is so well documented. Thanks again, I'm more quiet about my fishes now.



Out of curiosity, why you don't think results are not real? They are not "realistic" in some kind of sense?

Nitrification bacteria grows predictably. It doesn’t make sense that a population didn’t establish after adding live snail shells, coral skeletons, bottled bacteria, and live sand.

I think this "makes sense" because according to the thread, the OP was guided to use carbon dosing to establish the bio-filter....which getting back to your point, doesn't make sense.

@LuigiScReef98 I agree with others to stop worrying about nitrite. It's an artifact of the oddball startup method used, but thankfully not significant since no2 is not toxic. Things will eventually balance out.

But also I would encourage you to read a lot more and try not to depend on any one source for your "how to" info. Our hobby is very trendy...so it often takes some digging to get the best info. I suggest books to get your baseline knowledge and use internet to supplement.

 

[dvgyfresh]

A video that I was talking about , I learned a thing or two!

 

[rtparty]

There is ZERO reason to test nitrite. None. Not one. Zilch

Stop testing. Stop worrying and enjoy the tank

 

[rtparty]

Double post

 

[LuigiScReef98]

Thank you all guys

 

[twentyleagues]

I agree with nitrite being shown to not affect anything negatively in the ranges we would/could achieve in most tanks. I also like to know where and why my tank is at a certain place in the moment. What are you using to test? This may be an answer to the question.
Also this went under appreciated

The presence of nitrites, especially in that .3 range, SHOULD produce false high nitrate testing results..... That is why I am questioning these results.

You should also test phosphates.

Most nitrate tests will test multiple times higher when nitrite is present. So if its not it may be false point of worry.

The last part is also important if you have low or no phosphate the bacteria that use nitrite would not be able to do so. @Lasse probably has a better explanation than I do we have talked about this before. I delved down the nitrite rabbit hole during my dry sand/rock cycled current tank. My nitrites were many times higher than yours and even though I knew that they would not harm anything I still wanted a good full cycling bacterial population. Adding phosphates was the answer to my "issues". I could add phosphates and see a decrease in nitrites the next day and then a stall, add more phosphates and again a drop in nitrites and a stall when used. Until the nitrite level was 0 when tested I added phosphates. Once I had a reading of .06-.08 steady of phosphate I added it once I hit that reading without adding I stopped adding it. I have not been able to see a positive nitrite reading since using Hannah, api and Salifert tests.

All this probably doesnt matter in your case as I think your test is a false positive.

 

[LuigiScReef98]

I agree with nitrite being shown to not affect anything negatively in the ranges we would/could achieve in most tanks. I also like to know where and why my tank is at a certain place in the moment. What are you using to test? This may be an answer to the question.
Also this went under appreciated

Most nitrate tests will test multiple times higher when nitrite is present. So if its not it may be false point of worry.

The last part is also important if you have low or no phosphate the bacteria that use nitrite would not be able to do so. @Lasse probably has a better explanation than I do we have talked about this before. I delved down the nitrite rabbit hole during my dry sand/rock cycled current tank. My nitrites were many times higher than yours and even though I knew that they would not harm anything I still wanted a good full cycling bacterial population. Adding phosphates was the answer to my "issues". I could add phosphates and see a decrease in nitrites the next day and then a stall, add more phosphates and again a drop in nitrites and a stall when used. Until the nitrite level was 0 when tested I added phosphates. Once I had a reading of .06-.08 steady of phosphate I added it once I hit that reading without adding I stopped adding it. I have not been able to see a positive nitrite reading since using Hannah, api and Salifert tests.

All this probably doesnt matter in your case as I think your test is a false positive.

I use Tropic Marin for NO2 and NO3. For phosphates I use JBL, and never obtained something different from the minimum relevable (<0.02). So they can influence nitrites, interesting…

How does do you add phosphates?

 

[twentyleagues]

I use Tropic Marin for NO2 and NO3. For phosphates I use JBL, and never obtained something different from the minimum relevable (<0.02). So they can influence nitrites, interesting…

How does do you add phosphates?

Well there are diy phosphate dosing instructions with food grade phosphate adds. You can also get ready made aquarium phosphate products. I simply added some food that was known to be high in phosphates, Reefroids.
https://www.reef2reef.com/threads/diy-phosphate-dosing-recipe.1109919/for reference.

 

[Lasse]

The second stage (NO2 -> NO3) nitrification bacteria are an autotroph group of microorganisms. They need Phosphorous in the form of orthophosphate (PO4 in the water) in order to grow. A dry start can cause PO4 depletion and therefore can adding PO4 solve the problem with a nitrification that stops before the second step. The first step - NH3/NH4 to NO2 is probably mainly done by archaea (not bacteria) and they seems to be active with lower concentrations of PO4

A PO4 around 0.06 should be enough for the second step - probably even around 0.04 will be sufficient. Below 0.02 - I do not know

Sincerely Lasse

 

[LuigiScReef98]

Thank you, I’ll try to work on PO4.

 

[twentyleagues]

Thank you, I’ll try to work on PO4.

Its a good idea to have some level of phosphates. I like above .08 everything uses phosphates to grow. I "chose" this number since Hannahs resolution is +/-.03 so I should never be too low which is bad, higher can be dealt with easy enough. I honestly do not know if this will help you or not with your perceived problem. I still think it may be a false test since your nitrate tests so low.