High Nitrate

[French47]

Hi To All,

I have a big problem. My tank has been ticking along nicely for months, On Sunday I did my usual 40% water change, and yesterday ( Wednesday ) the Oto's and Pepers were hiding and very nervous, I did a water test Ammonia Zero, Nitrite Zero, Nitrate High !!!!!!, I have carried out another water change and will do another tomorrow and see if things improve. Any Ideas what's gone wrong the only change I have made recently is to go over to Tetra PlantaMin, could that be it?
Help.
Thank you

[Scleropages]

One thing to consider: your water supply may have had some nitrates in it when you did your last water change. Have you checked your tap/well water for nitrates lately?

[dw1305]

Hi all,

One thing to consider: your water supply may have had some nitrates in it when you did your last water change. Have you checked your tap/well water for nitrates lately?

It is difficult to test NO3 accurately, but you should be able to get figures from your water company (Southern Water?)

Because you are in Sussex (or anywhere else in the SE of the UK), it is quite likely that your water supply is close to the 50ppm NO3 EU limit at the moment.

As an example, I typed in "BN1 1NB" (Brighton sea-front) to the "Sothern Water" water quality page <https://www.southernwater.co.uk/homeAnd ... efault.asp> and the average NO3 value was 32 mg/ml NO3.

The water is also rated "hard". I use rain-water, I know people aren't keen on it, but I've never had any problems.

cheers Darrel

[Viktor Jarikov]

It is difficult to test NO3 accurately,

Darrel, can you please elaborate. Perhaps we read "accurately" differently. I've used an API liquid master kit NO3 test for years and trust it - I see when nitrites go higher and usually can rationalize why and take corrective actions which bring it lower. This two-bottle test ranges from 5 ppm to 50 ppm.

[dw1305]

Hi all,
You can't accurately measure nitrates with any kit you can buy off the shelf. In fact I'll go further than that you can't accurately measure nitrate levels, even with an ion selective electrode costing thousands of pounds. If any one tells you any different they are wrong.

The problem is that although you can create a standard curve from a known set of nitrate values (using KNO3 for example), even with colorimetric techniques, you don't get NO3- occurring on its own as the only anion in solution in tank water, and this creates a whole lot of other variables.

cheers Darrel

[Viktor Jarikov]

does this mean that our NO3 tests are useless?

i read often here and there someone says "my nitrates are 20, 40, 50 ppm..." and then a whole discussion ensues with even experts making conclusions about that person's fish-keeping practices and telling them to decrease their nitrates through water changes

I guess I should read up on what analytical reaction the API test uses and in general on NO3 analyses. I'd imagine spectroscopy, like infra-red, should show NO3 readily and quantitatively. Maybe atomic emission spectroscopy... or Nitrogen15 NMR (nuclear magnetic resonance spectroscopy) too... Tests like these cannot be more expensive than a few hundred $. Just thinking aloud.

[wrasse]

Maybe you need a bigger filter or a second filter on the tank.
Improve your filtration and doing wc's should lower nitrates.
You could also include nitrate filter media, if it's still a problem

[Flyfisher]

Hold on a minute!?!?!?
I may be wrong but I've always been with the understanding that nothing can reduce nitrates other than a water change or a healthy plant mass.
Adding filtration won't reduce your nitrates. Anyone back me up on that?? As I really ain't a water boffin /
Nitrate is the last phase in the dealing with ammonia cycle and nitrates don't change into anything else. They remain.
What adding filtration will do is slow down the ammonia and nitrite handling perhaps. But your nitrates being high, need that water change, so long as the tapwater isn't adding higher nitrates of course? But with all the uncertainty of test kits, I'd say they'll never give you the complete answer you're looking for.
Testing the tapwater is the first thing, but Im curious to know what kind of tank you have? Size? Volume? Filtration? Surface disturbance? Planted? High light? Low light? Co2 injected? Temperature? There's so much to consider when trying to fathom the mysteries of water. I've just about given up on it and I feel much happier for it now
But if you need to get to the bottom of this, add all the information and hopefully someone here can offer a logical solution.

Cheers

Gavin

[wrasse]

You're right Gavin, of course.

Lower nitrates with WCs and also plants 'feed' on it, which may lower it by having sufficient plants and/or fast-growing plants unless the nitrate build-up is faster than the plants can consume it. One can also add nitrate-absorbing media to filters.

Until/unless french47 gives more information there's little to go on.

The nervous fish after the wc suggest something is still wrong. Maybe the wrong dose of tetra plantamin was added... its a recent change to the tank.

Richard

[Flyfisher]

I think you've hit the nail on the head there mister Richard. Change! Fish just don't like it, whatever it is. You can keep most fish in most water, most tank environments etc etc. but change anything too suddenly and they all take the humph on ya!

[dw1305]

Hi all,

does this mean that our NO3 tests are useless?

Yes and no, if the test indicates you have some nitrate you probably do, but you can't really go a lot further than that. One reading of 50ppm is not the same as another of 50ppm, and may in reality be a much higher level. My suspicion would be that often test results of 10 or 20ppm are really an order of magnitude too small.

Most planted tanks will have a genuine approx. 10ppm NO3, even if you don't add any. What is interesting is that hi-tech planted tank enthusiasts are running tanks at very high added NO3 levels (80 - 100ppm) with apparently no effect on their livestock, suggesting that the damaging levels of NO3 we measure in conventional tanks, are a marker for the NH3 or NO2 that has been present, rather than NO3 being the toxic substance itself.

It was partially the problems with measurement of NO3 that led me to develop the "duck-weed" index.

cheers Darrel

[pleco_breeder]

Did I miss something here? What is the "duckweed index"?

Larry

[Viktor Jarikov]

Interesting food for thought. Thanks Darrel.

Yeah, Larry, I have no idea what that is either.

I wonder what French47 thinks of all of this. I fear he/she might have given up having found us not helpful.

[dw1305]

Hi all,

What is the "duckweed index"?

Sorry was in a bit of a hurry when I posted, it is jut a method of using a floating plant (this doesn't have to be duckweed) to give you an indication of the nutrient status of your tank. Details here: in "The Amazing Duckweed Filter" - <http://www.planetcatfish.com/forum/view ... 1&start=20>

I like to keep low nutrient levels in my soft water planted tanks and I use a conductivity meter and the colour/growth of Limnobium and Lemna as indices of this. If I have small, slow growing, pale green floating plants and a conductivity of about 100 microS, I know water conditions are pretty good."

I use this in conjunction with "estimation of BOD" (details in "wood for tanks?" - <http://www.planetcatfish.com/forum/view ... =4&t=35930> for tank maintenance.

I use the reduction of BOD (Biochemical Oxygen Demand) concept for tank water management, rather than saying something is "good" or "bad", you look at each item in terms of what nutrients it contains, how readily available they are, and how much effect it will have on BOD. A slice of sweet potato, or a prawn, will have much more potential to pollute than a much, much larger piece of wood, this is because they have readily available, soluble sugars and protein, that the wood doesn't, and therefore a higher BOD."

These are much more robust techniques for tank management than trying to rely on test results. This is true even if you have access laboratory analytical instruments, because by using these methods you are looking at the whole system "in the round", rather than at one or two test results that may be accurate.

You can think of using a test result as a basis for tank management like going to buy a pre-owned car and just making sure the tyres are pumped up and the windscreen wipers work, and not looking at anything else. These are things you need to know, but they aren't necessarily the ones you base your decision on whether to buy the car on.

cheers Darrel

[French47]

Sorry lads and Lassies, I am a bit behind with my response. I think one of my problems might be I am not used to tiny tanks, the one I have the problem with is a Fluval Edge 41 ltrs

I have been doing 50% water changes every week some times twice a week, I use Aqua Care water conditioner with the water change. So far I have lost 6 Oto's never found the bodies, the Pepper cats and the 2 Oto's spend most of the day Hiding about the only ones that have not changed are the White clouds and my 3 Akysis.
When I do a water change this weekend I shall take out the Biomax tubes and put in Seachem de-nitrate chemical filtration module.
I don't over feed, they get no food days and when I do feed it's frozen Bloodworm, Mysis shrimp and for the Minnows a pinch of Aqua care flake.
I am waiting for a water report from Souther water. After that it's sod it I will just grow plants in my small tank.
There you go, I have been keeping fish for 40 years I have breed discus and Angles and I have never had a problem like this.

[Viktor Jarikov]

Splendid-looking tank.

It does sounds strange to me too, I agree. Darrel points out and explains NO3 is a tough one plus I assume you used a strip test for NO3 since you provided no number (if yes, strip tests are notoriously unreliable) plus the tests have a shelf life/expiration date... Maybe your nitrates are not that high after all. Lets see what your sent-away test says.

[French47]

Thanks Victor for your reply and all the others who have taken time to write, well I did a tank test this weekend all back to normal, I had a report from the local water supplier and they say their water is on average P.H. 7.6 Nitrite 0 and Nitrate 17.07 mg no3 / l.
I just wonder if it was a one off dose of bad water when I did a change.
I guess I will never know.
Thank Guys.
Cheers

[dw1305]

Hi all,
Nice tank, you have a reasonable plant mass, although they slower growing plants. PM me if you want some Amazon Frogbit etc.

I had a report from the local water supplier and they say their water is on average P.H. 7.6 Nitrite 0 and Nitrate 17.07 mg no3 / l.

You really need to know the range of NO3 levels, the legal limit is 50ppm, but a lot of water companies often exceed this in the spring & early summer when a lot of nitrogen is being applied to silage & arable crops.

I just wonder if it was a one off dose of bad water when I did a change.

Emergency chloramine dosing is another possibility, again because the law is now very tight on "faecal coliform" bacteria levels, any break in the integrity of the water main (so basically any water main work) is likely to lead to a big dose of chloramine.

cheers Darrel