Help me understand nitrates

[Tripping Willow 91]

So I'm from the UK and my nitrates straight out the tap according to my API test kit vary from 10-20 to 20-40 ppm, they are usually a colour that's closely resembles 20ppm on the API chart, sometimes slightly higher and sometimes slightly lower but always around the 20 mark. To keep things simple we'll say my tap nitrates are 20ppm.

What I often hear and have been told on this forum is that nitrates should be a max of 20ppm and water changes are necessary to bring these levels down, obviously with my water I'm already at the max before I've even added any livestock and water changes with my tap water are never going to reduce nitrates to below 20.

When I've bought this up on UK forums a lot of people see no issues with my tap nitrates level, the reason being that they believe the nitrates in UK tap water tend to be non harmful inorganic nitrates mostly from fertilizer run off. But on a previous thread I started here I was told to use ro, a heavily planted sump, nitrates resins etc to help reduce my nitrates, all good ideas but RD. mentioned having previously seen on a UK forum that the US and UK measure nitrates differently.

Also, on a UK forum in the past I recall one of the moderators explaining that nitrate readings in UK tap water, are not taken using the same method as in the USA, and that 10 ppm US, is actually the same as approx 42 ppm UK. You might want to look into that as well.

I've been looking into nitrates a bit since that thread and I've found that different kits measure different things and this would explain what RD. saw on the UK forum.

The API kit I use measures nitrogen compounds in terms of concentration of the ion/compound, for nitrates this is no3-, whereas NT labs test kits measure nitrogen compounds in terms of nitrogen content, for nitrates this is no3-n. The difference between the two is a multiple of 4.43 (NT×4.3=API) so if my nitrates are 20ppm using API this would only be (20÷4.43) 4.5ppm using the NT labs kit. I've actually just ordered the NT labs kit so hopefully tomorrow or Sunday I'll be able to compare the readings of both and post pics of my results.

What I'd like to know is -
1 Do you have API kits in the US?
2 What is the most commonly used kit in the US and does it measure no3- or no3-n?
2 When people say keep nitrates below 20ppm are they referring to no3- (API) or no3-n (NT)?

Any information you can provide will be much appreciated.

 

[tlindsey]

So I'm from the UK and my nitrates straight out the tap according to my API test kit vary from 10-20 to 20-40 ppm, they are usually a colour that's closely resembles 20ppm on the API chart, sometimes slightly higher and sometimes slightly lower but always around the 20 mark. To keep things simple we'll say my tap nitrates are 20ppm.

What I often hear and have been told on this forum is that nitrates should be a max of 20ppm and water changes are necessary to bring these levels down, obviously with my water I'm already at the max before I've even added any livestock and water changes with my tap water are never going to reduce nitrates to below 20.

When I've bought this up on UK forums a lot of people see no issues with my tap nitrates level, the reason being that they believe the nitrates in UK tap water tend to be non harmful inorganic nitrates mostly from fertilizer run off. But on a previous thread I started here I was told to use ro, a heavily planted sump, nitrates resins etc to help reduce my nitrates, all good ideas but RD. mentioned having previously seen on a UK forum that the US and UK measure nitrates differently.

I've been looking into nitrates a bit since that thread and I've found that different kits measure different things and this would explain what RD. saw on the UK forum.

The API kit I use measures nitrogen compounds in terms of concentration of the ion/compound, for nitrates this is no3-, whereas NT labs test kits measure nitrogen compounds in terms of nitrogen content, for nitrates this is no3-n. The difference between the two is a multiple of 4.43 (NT×4.3=API) so if my nitrates are 20ppm using API this would only be (20÷4.43) 4.5ppm using the NT labs kit. I've actually just ordered the NT labs kit so hopefully tomorrow or Sunday I'll be able to compare the readings of both and post pics of my results.

What I'd like to know is -
1 Do you have API kits in the US?
2 What is the most commonly used kit in the US and does it measure no3- or no3-n?
2 When people say keep nitrates below 20ppm are they referring to no3- (API) or no3-n (NT)?

Any information you can provide will be much appreciated.

Yes most use API test kit in the US.
duanes
Rocksor
RD.

 

[Rocksor]

In the US, most freshwater fish keepers use API nitrate test. In doing so, we present our readings as NO3-, so in the US we are referring to keeping our NO3- below 20 ppm

 

[duanes]

In the US, most freshwater fish keepers use API nitrate test. In doing so, we present our readings as NO3-, so in the US we are referring to keeping our NO3- below 20 ppm

Agree
The MCL for nitrate in drinking water in the U.S. is 10ppm.
Most water systems in the U.S. don't come close to hitting that MCL.
In the facility where I worked as a chemist/microbiologist, the natural water (even before treatment(Lake Michigan raw water)) barely exceeded 1 ppm nitrate, (at least the way we measure/read it in the U.S.).
Maybe tests in the U/S. are read differently, than in the U.K..
The only places I've seen readings higher readings in the U.S., are rural areas where farms use extensive fertilization.

but.....To understand nitrate in aquariums one needs to look ate how it is viewed as as a whole in tandem with fish death in the aquarium industry.
Most community fish (where the ones is) are small tetras, live bearers, small anabantids, etc have a sgenerally short life span, maybe only 2 years in nature, 3+ in aquaria.
Because the chronic effects of nitrate often take 2 years to start to show up, nitrate is basically dismissed as a threat in those basic community settings, so a 20 ppm nitrate reading is not considered reverent to the profit margin.
And large cichlids, thought of as specialty fish, not relevant to most of the industry for research.
Most reseach is done on fish we consume and how, and how best to get it to market economically and quickly.
Only with more long lived fish, are the chronic effects noticeable, an Oscar or Uaru with HITH, or other (oft considered) other "mystery" diseases in aging cichlids.
And nitrate is not seen as the total culprit because its effects are often combined with other stressors that older, larger cichlids deal with (like a soft water fish being forced to exist in hard water, or overcrowded conditions in small tanks, or with improper tank mate combination.
Many of the bacteria associated with conditions ike HITH are pH sensitive (preferring a pH range of 7.5 +/- 0.5 , to 8.5 and mineral rich condition.

As an example
Fish from Amazonian waters have a naturally low pH range, and these fish have not had to evolve resistance in lower pH mineral poor water of that area to these bacteria, are often the first fish to show HITH symptoms in aquariums, but the symptoms are considered a mystery by many aquarists, because they are chronic, they sneak up (take so much time to make an appearance).
Most oscars only exhibit systems after 2 or more years old, after being subjected tothat period of living that long in nitrate soup

 

[Tripping Willow 91]

Yes most use API test kit in the US.
duanes
Rocksor
RD.

There goes my theory then ?

 

[fishdance]

It's a slippery slope. In commercial aquaculture a nitrate range of 0 to 200 ppm is considered low. Toxicity levels would be 1200 + ppm. Aquaculture is different from ornamental fish keeping but the economic value and desire for optimal growth is high.

Speaking as a hobbyist ornamental fish breeder, when I manipulate spawning by water change, it is beneficial to start with high nitrate and I generally run up to 400ppm in broodstock tanks before a water change trigger.

Commenting as a well travelled international fish keeper, it feels shameful knowing most of the developed western world water changes with pristine potable water. Our fish get better water than lots of people in some of the places I've been.

 

[Tripping Willow 91]

Agree
The MCL for nitrate in drinking water in the U.S. is 10ppm.
Most water systems in the U.S. don't come close to hitting that MCL.
In the facility where I worked as a chemist/microbiologist, the natural water (even before treatment(Lake Michigan raw water)) barely exceeded 1 ppm nitrate, (at least the way we measure/read it in the U.S.).
Maybe tests in the U/S. are read differently, than in the U.K..
The only places I've seen readings higher readings in the U.S., are rural areas where farms use extensive fertilization.

but.....To understand nitrate in aquariums one needs to look ate how it is viewed as as a whole in tandem with fish death in the aquarium industry.
Most community fish (where the ones is) are small tetras, live bearers, small anabantids, etc have a sgenerally short life span, maybe only 2 years in nature, 3+ in aquaria.
Because the chronic effects of nitrate often take 2 years to start to show up, nitrate is basically dismissed as a threat in those basic community settings, so a 20 ppm nitrate reading is not considered reverent to the profit margin.
And large cichlids, thought of as specialty fish, not relevant to most of the industry for research.
Most reseach is done on fish we consume and how, and how best to get it to market economically and quickly.
Only with more long lived fish, are the chronic effects noticeable, an Oscar or Uaru with HITH, or other (oft considered) other "mystery" diseases in aging cichlids.
And nitrate is not seen as the total culprit because its effects are often combined with other stressors that older, larger cichlids deal with (like a soft water fish being forced to exist in hard water, or overcrowded conditions in small tanks, or with improper tank mate combination.
Many of the bacteria associated with conditions ike HITH are pH sensitive (preferring a pH range of 7.5 +/- 0.5 , to 8.5 and mineral rich condition.

As an example
Fish from Amazonian waters have a naturally low pH range, and these fish have not had to evolve resistance in lower pH mineral poor water of that area to these bacteria, are often the first fish to show HITH symptoms in aquariums, but the symptoms are considered a mystery by many aquarists, because they are chronic, they sneak up (take so much time to make an appearance).
Most oscars only exhibit systems after 2 or more years old, after being subjected tothat period of living that long in nitrate soup

The MCL for nitrate in England is 50ppm and I believe this is no3- not no3-n as my water company gets the average reading for my postcode as 21.6ppm so very similar to what my API kit is telly me. Even if the tests by the water companies etc were read differently in the US and UK, we're all using API tests to check our water so we're all reading our results the same and most of you guys from the US seem to get 0 readings and I'm getting 20. If my high taps nitrates are from fertilizer run off, is this not much of an issue for fishkeeping? Do most people in the US drink their tap water?

 

[duanes]

(/Quote)
Commenting as a well travelled international fish keeper, it feels shameful knowing most of the developed western world water changes with pristine potable water. Our fish get better water than lots of people in some of the places I've been.
[/QUOTE]
Living in Panama, I see this quite a bit.
Our clinic is often lined up with patients plagued with gut type parasites
But....what's good for fish, and what's good for humans, is often very different.
When I measure nitrate in the natural water where I collect fish in, nitrate is usually undetectable.
I believe the thick foliage surrounding the lakes and rivers of the tropics, suck it up as fast as it is produced.

Above, Lake Gatun Panama.
Below a tributary of the Rio Magdalena, Colombia