Ammonia in water can be toxic at elevated concentrations. The few studies that have been carried out on the toxicity of ammonia to freshwater vegetation have shown that concentrations greater than 2.4 milligrams of total ammonia (i.e., ammonia plus ammonium) per litre inhibit photosynthesis and growth in algae (e.g., World Health Organization 1986). In experiments with rooted aquatic plants, ammonia reduced the length and weight of roots and shoots (Stanley 1974; Litav and Lehrer 1978). There have been no conclusive toxicity tests on saltwater plants.

In most surface waters, total ammonia concentrations greater than about 2 milligrams per litre are toxic to aquatic animals (Mueller and Helsel 1996), although this varies among species and life stages.

Although nitrates in water are relatively non-toxic, nitrate concentrations in the range of 5–50 milligrams per litre have been shown to be lethal to eggs and, to a lesser extent, fry of salmon and trout species (Kincheloe et al. 1979).

These tend to be the most sensitive species as well as developmental stages.
If fish are able to breed and raise fry, then it itvery likely there is little if any impact upon the fish at a particular NO3 ppm level. This is the lowest range for any NO3 toxicity fish species that could be found and does not apply to warm water fish. Even still, the range is quite large evene the worst case senario, up to 50ppm but as low as 5ppm for the most sensitive stage and species.

Pierce et al 1993 suggested:
Previous studies have indicated that long term exposure to nitrate-N levels above 100 mg/L may be detrimental to fish. This study was undertaken to assess the acute toxicity of nitrate to five species of marine fish, while efforts were taken to reduce the nitrate concentration in the recirculating systems.

Marco 1999, suggests that warm water species have a suggested range of "recommended levels of nitrate for warm-water fishes (90 mg N-NO3-/L)"

That's N as NO3, so 4.4X 90.

Quite high.

here's a link to the common fathead minnow:
SETAC Journals Online - ACUTE AND CHRONIC TOXICITY OF NITRATE TO FATHEAD MINNOWS (PIMEPHALES PROMELAS), CERIODAPHNIA DUBIA, AND DAPHNIA MAGNA

Do the math for the conversion of N-NO3 to NO3 for ppms.

Quite high huh?

Still not convinced?

Well take a long look at the Fish and NO3 toxicity section in this good review paper:

http://www.s2.chalmers.se/~tw/DOWNLO...ate_limits.pdf

Remember to multipy by 4.4 to get NO3ppms rather than N-NO3!

As you can see, the ranges are extremely high and that warmer water fish tend to have a greater ability to withstand NO3 levels as well. When fish breed and fry ar eproduces, this representst the behavior(positive good) and the most sensntive life stanges. I routinely have this occur in such higher NO3 tanks.

Now some have made claims that my advice concerning EI dosing is bad for fish and they have not supported with test, with primary research, nor applied plant tank experience neither over short term nor over long term test.

Now I ask them to stand before others to show their evidence rather than preceptions to show and prove otherwise.

What I hear from:

1. Banther about less is better(but they rarely say how much less)
2. No supporting primary research(still waiting for one review)
3. Advice and heresay from other web sites
4. Toxicity citations about humans, not fish
5. No toxcity test of their own to deny/confirm(kind of sad, they make claims and then do not test them)
6. Claims that behaviors change(how do we measure this?)

The burden of proof is upon the critic here.
I've done my job supporting my advice, the real question folks should ask: have the critics done their job supporting theirs?

I just don't see it.
They get irritated when I go after them about it and they scramble, take it personally etc, but the bottom line is not a personal issue, it's about the fish, the hobby and the methods we use the advice that is given.

I do not roll over and accept their criticism when it's plainly wrong.

Should I?

Regards,
Tom Barr

Count me in as one of the dissidents as I've kept discus and have bred Apistogramma species in high light EI tanks. I would guess most of the "observed" toxicity was due to NH4 and perhaps blamed on NO3.

As with so many of these journals though I struggle with some of the terms, the first of which is N-NO3. Could you explain how this is formed and why both papers focus on this form?

The Chemosphere article also presents their data in terms of the Toxicological parameters " NN h LC50" "NN h LC10" and " NN h LC0.01" Could you clarify what these parameters mean?

Cheers,

N-NO3 is Nitrogen ppms as NO3.

So if they say 10ppm as N-NO3, you have to multiply by 4.42 to get NO3 ppms, or 44.2 ppm NO3.

This is because they are measuring only nitrogen, not NO3.
N = 14 grams /mol
NO3 = 62 grams/mol

Thus 62/14= 4.42 to get NO3 ppms

Same deal with the Lamott and many other test kits.

So those reported values are extremely high!!!

LD = lethal dose.
LD 50 means the time required for 50% death and LD10 =10% death and LD 0.01 = 0.01% death etc.

The last paper on the 3rd table is really good.
Read the rest of it though.

Ask questions and I'll try and answer till you get it.

This stuff is dense reading, I know it's not the fun type of Harry Potter stuff here

Regards,
Tom Barr

Sorry, this is still confusing to me. They use the term NO3-N. Is it the same as N-NO3?

As per US EPA the MCL for drinking water is 10ppm NO3.


The paper from Camargo/ Alonso/Salamanca says:

"A nitrate concentration of 10 mg NO3-N/l (USA federal maximum level for drinking water) can adversely affect..."

What is correct?



Regards,
Detlef

N-NO3 or NO3-N is still 4.42X less than NO3ppm.
Unless it's NO3 alone, it's the fraction.
P-PO4 or PO4-P, same deal.

Humans are not fish.
The US EPA has no maximum NO3 ppms for aquatic life(the topic here).

10 ppm is 10x 4.42 or about 44-45ppm NO3, not 10ppm.

Citing human health issues with tap water has no bearing, relationship and no support for fish toxicity.

I've seen folks bring this one(drinking water MCL's) up for support about high NO3 levels being "bad"(more recently at TPT), but it is not support at all. If you read the article closely you'll see that the US EPA has no ppm critieria for aquatic life, just for NO2 and NH4.

There massive evidence that the ranges of NO3 that are detrimental are very high and they are also in line with observations from folks that have dosed higher NO3's for long time frames, in line with EI dosing, toxicity test using more sensitive species such as invertebrates like shrimp as well as toxicity specific for dosing KNO3.

Much like the falsification approach used in showing excess PO4 or NO3 does not induce algae, same deal here.

You add it to the suspected deterimental levels.
But what do you use to measure poor fish health/behavioral changes?
With algae, it's easy: algae bloom or not/plant health
With fish, a good indicator of both health and behaviore is reproduction(breeding/fry rearing).

That is the most sensitve stage and since my fish, as well as others keep breeding even in light of higher NO3 ppms, I little choice but to conclude such advice about lowering being better or higher levels being detrimental to be unfounded.

Now folks have plenty if issues with fish and kill them all day long on the forums for many reasons, with or without planted tanks that do not dose KNO3 or have higher NO3 levels also.

So if you use a control, it has to be one based on a success, not failure.
The hypothesis that "higher NO3 from KNO3 is bad" fails, but not the fish or the stability of the tank!

Same thing with the PO4 and algae test.

You need a control tank that isolates the dependent variable.
It must be stable to begin with and you must be able to add it and see the negative response each time over and over again(5-6x etc).
Many folks cannot do this or do not want to do this. Many would rather whine and cry or accuse me or others of bad advice without offering any support. So they think I and and other folks are crazy.

They use correlation, they use circumstantial evidence as support for what they believe is right, not the sandard: "beyond a reasonable doubt".

All I have to do is show under a number of conditions and over time that these same ppms of NO3 do not cause any helath or reproductive issues for a wide range of tropical fish. That falsifies the hypothesis. Thus it cannot be correct.
I know I have done this beyond a reasonable doubt. There are far more other plausible reasons that the critics have fish health and reproductive issues than NO3 from KNO3.

That's easy to test and measure because it's one thing.
Trying to see every single person has fish health issues or reproductive fish issue is literally impossible.

So......... I test one thing at a time and get to know that well.
Keep it simple and isolated so you can control things.



Regards,
Tom Barr

OK I found the correct numbers. The EPA made a mistake in one of their online papers I found while googling along. It had confused me in what they say here:

EPA Ground Water & Drinking Water > breadcrumb? > Consumer Factsheet on: NITRATES/NITRITES

"The MCL for nitrates has been set at 10 ppm, and for nitrites at 1 ppm, because... "



Another EPA online paper states correctly. It can be found here:

Nitrate Rule - U.S. EPA REGION 8

"How Much Nitrate Is Too Much Nitrate?

The EPA has established a maximum level of nitrate concentration in drinking water from a public water supply that is safe for human consumption. That level or standard is: 10 milligrams per liter of nitrate - nitrogen (NO3-N) or its equivalent of 45 milligrams per liter of nitrate (NO3)."


Over here in Germany they went a little higher and limited NO3 to 50ppm. No lethal casualties of grown-ups have been reported so far Though drinking water for babies should be kept lower they keep on warning.

Thanks Tom! Still wondering why they make such mistakes.....

Best regards,
Detlef

Another question about ammonia/ammonium. I'm not a chemist, but my understanding is that ammonia, NH3 is a gas at normal pressure and temperature. If you add it to water, it dissolves into ammonium NH4+ and OH- ions, just as a salt dissolves into ions in water. So, there can be no ammonia in water, only ammonium. (NH3 + H20 = NH4+ + OH-) Is this correct? I ask because I have been told that ammonium is ok, but ammonia is bad, and I can't see how that can be.

I think because all of us folks make mistakes, like entering in data and writing.
When the issues are critical, then you need to double check and make sure, sort of like calibrating a test kit.

Heck, I make them all the time myself
But I check up on the ones I think are critical.

I know what they mean generally so I can typically figure out what is meant.

Regards,
Tom Barr

The issue is addressed here:

Ammonia, water quality and fish health

Bacterial gill disease. Diagnosis and treatment

Toxicity and pH:

Ammonia Toxicity

Neil's table taken from a reference:
Re: ammonia (NH3) vs. ammonium (NH4+)

Unionized NH3 is very toxic.

Regards,
Tom Barr

I provided the trout egg and fry data as well. This is to show the lower side, but Trout are an exception.

But...........this is not the same as our fish nor are they nearly as tough. They require very clean pure water for development. They require very high O2 levels and cool water.

The guppy fry data showed about 800-900ppm of NO3 before toxicity for a 3 day LD50 occured and longer term test have been done also.
Still, a guppy is a tough fish.

However, I'm not going to measure 500-1000ppm of NO3, that's just way too far outside any mess up ranges one might ever encounter using KNO3.

The point about the trout and toxicity is that some species are sensitive and we should not assume that all fish are going to respond well, but with Discus and Apistos and Altums responding well, as well as Rose lines and other wild so called sensitive fish, I hardly see a need.

What we need is someone to show that due to KNO3 dosing at higher levels, say 50-80ppm is really deterimental to breeding and fry.
Or say 30 ppm vs 10ppm of NO3 will make a difference.

That's the critic's argument, they claim there's a huge difference and it's ethically irresponsible. I guess when you have no factual evidence to support your agenda, ethics starts looking like a good tangent to try to argue from and question me from.

Tom Barr has bad eithics because he suggests this, rather than seeing if what I've said has merit. One clown claimed that EI dosing was ecologically irresponsible since it adds NO3/PO4 to the water ways.

I suggested that they bike instead of drive/more and not keep aquaria at all, nor maintain lawns, dump endocrine disruptors into the waterways amongst other far more significant issues.

The differences between the dosing patterns is not going to make a difference and a well run waste water treatment plant easily handles both PO4 and NO3 from it's effluent, that is.........what they are designed to do

I'm wondering what new issue some clown will come up with next to suggest testing the tank is good/required, that adding fertilizers are bad, that excess PO4/NO3 are unethical, cause algae, bad for fish.

For the last 10+ years I've heard all sorts of baloney.
No one actually testing and saying "no, this is wrong, here's why and here's how to show it, here's the method we used to measure and test it. Here's the evidence" etc.

I never get that. I never get long term studies, I never get practical test they tried to show support their on assertions.

They get cut to pieces in the post.
Then I'm a bad guy for not having compassion and don't sugar coat and pussy foot around their feelings. Sorry, I aint going to have compassion for folks who are full of crap and want to attack me personally. If they do not like it, then they need to learn not to attack people personally and stick to the topic.

I had this debate years ago on the APD, but the crowd was more inclined to test and measure and see. They could look things up and see. There was far less debate about fish health due to that.

There's a a few reason's why this debate has come up again however.
I'm still here and the evidence is even better and stronger today.
They will have an even harder time showing this today than they did years ago.

Regards,
Tom Barr