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Acceptable level of Nitrate non planted community.

DogTailRed2

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I run around 20-40ppm on my community tanks (unless I use Nitra Guard when it's 0-5ppm).
What's the accepted norm for Nitrate and at what point does it become an issue?
 
20 -40ppm is good as it's around 30 that we EI users aim for, lean dosers will no doubt argue this point and it's presuming you have plants in these aquariums.
Cheers!
Sorry, just re-read the title (old age), as far as I'm aware the levels should be ideally kept below 25, and below 5 would be perfect.
 
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Hi all,
The simple answer is <"plant the tank"> and your high nitrate (NO3) levels are over. I'm a floating plant fan, mainly because they have <"Diana Walstad's "aerial advantage"">
What's the accepted norm for Nitrate and at what point does it become an issue?
Difficult to say really, the NO3- ion doesn't probably <"become an issue"> until you're are in the hundreds of ppm.

In a non-planted (like below) tank levels will <"inevitably rise"> without water changes, anaerobic denitrification or <"anion exchange resin">.

n-cycle.gif

cheers Darrel
 
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What's the water you are putting in? If you are using tap that is 40ppm to start then I'd say you are doing well. If your input is 0ppm then you could increase water changes a bit to bring it down.
 
What's the accepted norm for Nitrate
Rather an emotive subject and the answers you'll get will vary greatly.

As pointed out above nitrate itself isn't overly toxic to fish, the toxic part comes via ammonia and nitrite ( the nitrogen cycle.) If you surf the Web the figures for safe nitrate levels accumulating via this cycle will range from 5ppm up to 80ppm, I wouldn't suggest you run a tank at the high end of this scale and suspect the low range number is in part fueled by the multi million pound industry that profits from folks trying to keeping nitrates low.

I would imagine the 20 to 40ppm range you are aiming for is acceptable, i've certainly maintained fish only tanks at far higher levels than this in the past and fish health over the years wasn't compromised.
 
What's the water you are putting in? If you are using tap that is 40ppm to start then I'd say you are doing well. If your input is 0ppm then you could increase water changes a bit to bring it down.
My tap water is 25ppm.
 
Rather an emotive subject and the answers you'll get will vary greatly.

As pointed out above nitrate itself isn't overly toxic to fish, the toxic part comes via ammonia and nitrite ( the nitrogen cycle.) If you surf the Web the figures for safe nitrate levels accumulating via this cycle will range from 5ppm up to 80ppm, I wouldn't suggest you run a tank at the high end of this scale and suspect the low range number is in part fueled by the multi million pound industry that profits from folks trying to keeping nitrates low.

I would imagine the 20 to 40ppm range you are aiming for is acceptable, i've certainly maintained fish only tanks at far higher levels than this in the past and fish health over the years wasn't compromised.
I've always run about 40ppm on average without issues.
I started to use Nitra Guard which brings it down to zero or .5ppm. I'm just weighing up wether the cost outweighs any disadvantages.
 
Hi all,
The simple answer is <"plant the tank"> and your high nitrate (NO3) levels are over. I'm a floating plant fan, mainly because they have <"Diana Walstad's "aerial advantage"">

cheers Darrel
The problem I have with plants with my 450 litre aquarium is boistrous fish (Clowns and Loaches) and feed.
Ideally I need plants that are tough and hardy. Can't be uprooted and don't need much feeding.
I might try floating but they can become problematic in a short space of time (overgrowing the tank quickly like fairey moss).
 
Hi all,
I might try floating but they can become problematic in a short space of time (overgrowing the tank quickly like fairey moss).
In nitrate terms that is a good thing, not a bad one.

Fairy Moss (Azolla caroliniana) and Duckweed (Lemna minor) are a <"pita to get out of the tank">, but other floaters like Salvinia "auriculata" (Water fern), Pistia stratiotes (Nile Cabbage) and Limnobium laevigatum (Amazon Frogbit) are much easier to control.

I <"really like"> Amazon Frogbit, partially because you can use it for the <"Duckweed Index">.

cheers Darrel
 
I've always run about 40ppm on average without issues.
I started to use Nitra Guard which brings it down to zero or .5ppm. I'm just weighing up wether the cost outweighs any disadvantages.

Actually you are in the best position to know whether Nitraguard has benefited your aquarium... after you installed nitraguard, what benefits have you witnessed?
 
The simple answer is <"plant the tank"> and your high nitrate (NO3) levels are over.
Hi @dw1305

It seems that aquatic plants would rather uptake ammonium in preference to nitrate. Diana Walstad covers this in her book* on page 107. So, presumably, there could come a point at which nitrate production (primarily in the bio filter) exceeds nitrate consumption by plants. Production of nitrate, of course, is the final stage in the nitrification process. Therefore, caution would need to be exercised between fish stocking density (ammonia producers) and quantity of established plants. Of course, water changes are one way of controlling nitrate build-up.

* Ecology of the Planted Aquarium

JPC
 
Hi all,
It seems that aquatic plants would rather uptake ammonium in preference to nitrate. Diana Walstad covers this in her book* on page 107.
I think most plants will take up ammonium (NH4+) preferentially, just because it requires less energy input. (<"Comparison of four aquatic plant treatment systems for nutrient removal from eutrophied water">)
So, presumably, there could come a point at which nitrate production (primarily in the bio filter) exceeds nitrate consumption by plants. Production of nitrate, of course, is the final stage in the nitrification process.
This is really going to depend on the fish stocking density and the amount (and nature) of the planting. There definitely are situations where stocking density would preclude getting enough plant biomass into the tank with the fish, you would need <"some spatial separation">. This is also where <"Diana Walstad's "aerial advantage"> comes into play. <"Turned up to eleven"> plants, with access to atmospheric CO2, are always going to be able to assimilate more fixed nitrogen.
Therefore, caution would need to be exercised between fish stocking density (ammonia producers) and quantity of established plants.
It is back to the <"one-legged Irishman">. I'll use the "all you can eat buffet" as an analogy. You may start with the Pork ribs, but once they've gone, and you are still hungry, you aren't going to turn the Vol au vents down.

cheers Darrel
 
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What's the accepted norm for Nitrate and at what point does it become an issue?
Hi @DogTailRed2

Trying to get definitive figures for nitrate toxicity in our hobby is like finding water in the Sahara Desert. So, that means looking elsewhere. Please find attached:


You'll find the figures broken down into two categories - acute (short term) and chronic (long term). Please note that the figures are given as NO3-N and will therefore need to be multiplied by 4.43 to convert to NO3. I suspect that the chronic figures are of greatest interest to we aquarists.

Please note that I'm no expert in this aspect of aquatics. It's just that I read a lot!

JPC
 
Hi all,
You'll find the figures broken down into two categories - acute (short term) and chronic (long term). Please note that the figures are given as NO3-N and will therefore need to be multiplied by 4.43 to convert to NO3. I suspect that the chronic figures are of greatest interest to we aquarists.
That is the question really, "what are the long term (chronic) levels of NO3 that are deleterious to fish health?"

It gets a bit of a run through in <"What are your nitrate - guzzling plants?">. The whole thread is worth a read.

cheers Darrel
 
Hi @dw1305

but at what level, if any, does nitrate pose a problem to aquatic plants?

JPC
Hi @jaypeecee, Very interesting question. You can definitely scorch (and kill) terrestrial plants and grasses with fertilizer (presumably nitrate). I don't know if you can get to an equivalent situation in a planted tank - I suppose you would need pretty extreme levels, if at all.

Cheers,
Michael
 
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Hi all,
You can definitely scorch (and kill) terrestrial plants and grasses with fertilizer (presumably nitrate). I don't know if you can get to an equivalent situation in a planted tank - I suppose you would need pretty extreme levels, if at all.
It would depend <"on the plant"> to some degree. I'm not sure you could ever get there with a <"turned up to eleven plant"> like <"Eichornia crassipes">*
When we discuss nitrate toxicity, we invariably refer to livestock but at what level, if any, does nitrate pose a problem to aquatic plants?
What @MichaelJ says. We have a few threads on <"fertiliser burn">, although they mainly relate to DSM set-ups.

* Hongjie Q., et al. (2016) "Site test of phytoremediation of an open pond contaminated with domestic sewage using water hyacinth and water lettuce">, Ecological Engineering" 95, pp 753-762

cheers Darrel
 
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