• You are viewing the forum as a Guest, please login (you can use your Facebook, Twitter, Google or Microsoft account to login) or register using this link: Log in or Sign Up
  • You can now follow UKAPS on Instagram.

Nitrate (NO3) to Nitrogen? Possible? My tank

demetrisag

New Member
Joined
20 May 2021
Messages
21
Location
Cyprus
Is it possible to have bacteria that convert No3 to pure nitrogen? As my tank goes through Nitrogen cycle. It goes very well. I would put plants by now but because of various reasons I didn't. Lately though, after dosing pure ammonia, it goes through the regular stages (ammonia, nitrite and nitrates) but when I test nitrates they are very low to 0 when I expect them to be much higher. Is it possible I developed bacteria that also convert NO3?
 

PARAGUAY

Member
Joined
13 Nov 2013
Messages
2,175
Location
Lancashire
Its just not cycled yet IMO.Get your plants in as soon as you can much better way to cycle an aquarium
 

ScareCrow

Member
Joined
28 Jan 2019
Messages
229
Location
South west
The consensus is that the test kits aimed at the fish keeping market are inaccurate. There are several posts around this but the following should give you a good start: What about test kits?

The other point is our understanding of nitrification in our aquariums has changed. I believe the previous science was based on processes, which took place in sewage treatment. The types of filtration employed by sewage treatment plants differ both in size and technique, compared to what most people use in home aquaria. The following thread and links within it will give the full answer to your question: Good review article on ammonia oxidation
 
Last edited:

demetrisag

New Member
Thread starter
Joined
20 May 2021
Messages
21
Location
Cyprus
The tank is definitely 100% converting ammonia to nitrite (tested with seachem ammonia alert & jbl ammonia test) also tested against clean water for more certain results. And the tank is definitely converting nitrites to nitrates cause there are like loooooots of nitrites in the water (tested with jbl nitrite test with aquarium water and clear water several times, looots of nitrites. Gets pink straight away) that then get converted to nitrate. But then after a day or so nitrates go away. Is it possible?
 

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
12,204
Location
nr Bath
Hi all,
The tank is definitely 100% converting ammonia to nitrite (tested with seachem ammonia alert & jbl ammonia test) ...........But then after a day or so nitrates go away. Is it possible?
Yes, it is definitely possible. You can get anaerobic denitrification in the substrate, and possibly in the filter as well in certain circumstances.

Have a look around the forum, and you should be able find a more complete discussion about cycling, oxygen, filter media, NO3 test kits etc.

Cheers Darrel
 

erwin123

Member
Joined
4 Mar 2021
Messages
123
Location
Singapore
there are some plants that turn red in response to nitrate limitation. the colouration of these plants may help you confirm your test reading that the nitrates in water column are zero.
 

Andy Pierce

Member
Joined
27 Nov 2020
Messages
138
Location
Cambridge, UK
Is it possible to have bacteria that convert No3 to pure nitrogen? ... when I test nitrates they are very low to 0 when I expect them to be much higher. Is it possible I developed bacteria that also convert NO3?
I'm pretty skeptical this ever actually occurs in any type of real-world aquarium set-up. Denitrification in the substrate would result in production of gas bubbles exiting the substrate, but I have not observed this or seen any credible reports including from people marketing substrate that allegedly carries out this process. There are specialised anaerobic denitrification filter designs (https://www.epa.gov/sites/productio.../denitrifying_filters_fact_sheet_p100il79.pdf) but this is not the sort of thing you will accidentally create with your aquarium filter, which if anything is designed for deliberate oxygenation to convert ammonia to less toxic oxidised chemical species (nitrite, nitrate).

Much more plausible is that you're experiencing first-hand the notorious unreliability of LFS supplied nitrate test kits.
 

demetrisag

New Member
Thread starter
Joined
20 May 2021
Messages
21
Location
Cyprus
How much notorious could they be? I am not counting ppm but extremes. Like There is a looooot of it and then there is absolutely non
 

dw1305

Expert
UKAPS Team
Joined
7 Apr 2008
Messages
12,204
Location
nr Bath
Hi all,
How much notorious could they be?
There are a number of issues that can occur with nitrate (NO3-) testing. These can affect both <"test kits and ion selective electrodes">.
there are some plants that turn red in response to nitrate limitation. the colouration of these plants may help you confirm your test reading that the nitrates in water column are zero.
I use this approach, but recommend Amazon Frogbit (Limnobium laevigatum) as my nutrient indicator. It has the advantages of:
Denitrification in the substrate would result in production of gas bubbles exiting the substrate, but I have not observed this or seen any credible reports including from people marketing substrate that allegedly carries out this process.
You definitely can get <"anaerobic denitrification in the substrate">. This wasn't <"exactly a substrate">, but it illustrates what can happen.
which if anything is designed for deliberate oxygenation to convert ammonia to less toxic oxidised chemical species (nitrite, nitrate).
That is the important bit. As far as I'm concerned making sure that the <"oxygen supply always exceeds the oxygen demand"> is one of the fundamental rules of filter design and management.

cheers Darrel
 
Last edited:

demetrisag

New Member
Thread starter
Joined
20 May 2021
Messages
21
Location
Cyprus
ok I think I know what happened, Algae started growing on my driftwood but it wasnt very visible at first so I guess algae would suck all the nitrates
 

Soilwork

Member
Joined
22 Nov 2015
Messages
496
I'm pretty skeptical this ever actually occurs in any type of real-world aquarium set-up. Denitrification in the substrate would result in production of gas bubbles exiting the substrate, but I have not observed this or seen any credible reports including from people marketing substrate that allegedly carries out this process. There are specialised anaerobic denitrification filter designs (https://www.epa.gov/sites/productio.../denitrifying_filters_fact_sheet_p100il79.pdf) but this is not the sort of thing you will accidentally create with your aquarium filter, which if anything is designed for deliberate oxygenation to convert ammonia to less toxic oxidised chemical species (nitrite, nitrate).

Much more plausible is that you're experiencing first-hand the notorious unreliability of LFS supplied nitrate test kits.

For what it’s worth I think I most definitely had anaerobic denitrification occurring in this tank.

My hypothesis is that, since according to the ‘Ecology of the Planted Aquarium’ by Diana Walstad, hydrogen sulphide production occurs at a much lower redox potential than denitrification and the unmistakable stench of sulphur was so putrid when I finally took this tank down I had to leave the living room, I must have definitely had a redox potential low enough to support Denitrification.
 

Attachments

  • 690C3398-C014-4F46-A8D7-1B9C4E8D380A.jpeg
    690C3398-C014-4F46-A8D7-1B9C4E8D380A.jpeg
    697.7 KB · Views: 11

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,990
Location
Bracknell
Is it possible to have bacteria that convert No3 to pure nitrogen? As my tank goes through Nitrogen cycle. It goes very well. I would put plants by now but because of various reasons I didn't. Lately though, after dosing pure ammonia, it goes through the regular stages (ammonia, nitrite and nitrates) but when I test nitrates they are very low to 0 when I expect them to be much higher. Is it possible I developed bacteria that also convert NO3?
Hi @demetrisag

Interesting. Please tell us more about the 'pure ammonia' that you used. And, did you use tap water plus a tap water conditioner? If so, which conditioner? Are you able to let us have more details about the water - such as KH, GH and pH, for example? I'm wondering if your water company adds any water treatments that are interfering with the test kits. I think it would be worth discussing your findings with them. May I also ask - did you use a bacterial starter culture? If so, which? An approximate timeline of all events would also be helpful.

In answering your initial question, it is possible to have denitrifying microbes that convert nitrate back to nitrogen but this normally happens anaerobically, i.e. in the absence of oxygen.

There are some reliable hobbyist nitrate test kits and the JBL liquid test kit is one such example. It's a different story with many test strips.

JPC
 

demetrisag

New Member
Thread starter
Joined
20 May 2021
Messages
21
Location
Cyprus
Guys as I said, I believe because I started developing algae in my driftwoods, algae was the reason my nitrates were near zero when they should have been way much higher. To answer jaypeecer questions though.

1. The ammonia I brought from farmacy, it's not cleaning or household ammonia, it's just a white bottle writing 24.5% ammonia.

2.I used tap water with tap conditioner. The first time I used seachem prime by accident (when I first put the water) but after that only jbl biotopol as prime also neutralizes ammonia.

3. The water is 20dGH - 17dKH and 7.9 ph but because I used tropica soil dKH was going very low. I don't know if they add anything to water but test kits with were pretty correct, I know that because I made a lot of comparisons with aquarium water, tap water, osmosis water like a looooot and where getting the "expected" results everytime.

4. The whole tank cycling so far it's 3 weeks and a half. I used seachem stability as starter bacteria at first and when dosed ammonia by end of week one all amonia was disappearing. The nitrites though where way more difficult by end of week two I wouldn't see any significant different (even though there was) so I put jbl dennitrol as well with seachem stability to boost it! End of week 3 everything was running fine! Start of week 4 when I was expecting to see 25-35ppm No3 I saw near 0 that's when I asked here!

But now I think that the development of algae I saw in my tank later was the reason for the No3 drop.
 

jaypeecee

Member
Joined
21 Jan 2015
Messages
1,990
Location
Bracknell
Hi @demetrisag

Thanks for the information. I think your conclusion - that the growth of algae consumed available nitrate - makes a lot of sense. Have you now removed the algae?

JPC
 
Similar threads
Thread starter Title Forum Replies Date
M Nitrate tests? General Planted Tank Discussions 18

Similar threads

Top