A Deep Dive on Ammonia Neutralizer Chemistry - Prime, ClorAm-X, Rongalite and friends.

[Formulator]

It is a classic reaction, which is why it came to mind as soon as formaldehyde was mentioned.

Ammonia would also react with the bisulfate to ammonium and sulfite. But the experimental research here has already taken a deep dive into separating NH3 from NH4+ for measurements I think.

So I am back to being clueless. I’m starting to lean more towards Seachem taking a theoretically sound reaction mechanism and applying it to a non-ideal system without appropriate experimental evidence or testing. The organic soup of our tank water is a really messy place to do theoretical organic chemistry…

 

[Dan_P]

What is particularly interesting, considering the data, is that the product of my proposed reaction between formaldehyde and NH3 is an uncharged amine base, methenamine. So theoretically it could pass through your gas membrane test disc and induce a pH change thus registering as NH3 with those discs (if I understand the mechanics of the disc tests correctly).

The ammonia sensing films contain a pH sensitive dye that turns blue in the presence of ammonia. If the pKa of a proposed interfering molecule is similar to ammonia, yeah, it would “fool” the sensor. An example of such a molecule is methylamine. The formaldehyde imine pKa is lower than ammonia and I would not expect it to be detected by the film.

 

[Randy Holmes-Farley]

FWIW, Seachem makes this very strong claim:

https://forum.seachem.com/forum/general-discussion/1708-prime

"Prime does not contain any formaldehyde. It is a proprietary aqueous solution of complexed hydrosulfite salts. I hope this helps!"

"any" is a very strong word, but i doubt they literally mean it. Even coca cola probably has "some" (which is a very weak word on the scale of 10^25 molecules in a can. .

They also say:

"
"The classical reaction of ammonia with formaldehyde to form methenamine is the principal of most ammonia removing conditioners. It may be used either directly or as a bisulfite complex. The bisulfite formaldehyde complex has the advantage of odor control, enhanced reaction time, and improved methenamine stability."

This is the principal of MOST water conditioners, but not ours. The active ingredient in Prime is very similar and functions in the same manner, but does NOT contain formaldehyde."

 

[Dan_P]

It is a classic reaction, which is why it came to mind as soon as formaldehyde was mentioned.

Ammonia would also react with the bisulfate to ammonium and sulfite. But the experimental research here has already taken a deep dive into separating NH3 from NH4+ for measurements I think.

So I am back to being clueless. I’m starting to lean more towards Seachem taking a theoretically sound reaction mechanism and applying it to a non-ideal system without appropriate experimental evidence or testing. The organic soup of our tank water is a really messy place to do theoretical organic chemistry…

Also wondering about the half-life of formaldehyde in aquarium water. Maybe @taricha has that data.

 

[Malcontent]

One thing I'm wondering...if all these products have the same ingredients why do only the Seachem versions have a reputation for stinking?

 

[Dan_P]

FWIW, Seachem makes this very strong claim:

https://forum.seachem.com/forum/general-discussion/1708-prime

"Prime does not contain any formaldehyde. It is a proprietary aqueous solution of complexed hydrosulfite salts. I hope this helps!"

"any" is a very strong word, but i doubt they literally mean it. Even coca cola probably has "some" (which is a very weak word on the scale of 10^25 molecules in a can. .

They also say:

"
"The classical reaction of ammonia with formaldehyde to form methenamine is the principal of most ammonia removing conditioners. It may be used either directly or as a bisulfite complex. The bisulfite formaldehyde complex has the advantage of odor control, enhanced reaction time, and improved methenamine stability."

This is the principal of MOST water conditioners, but not ours. The active ingredient in Prime is very similar and functions in the same manner, but does NOT contain formaldehyde."

This feels similar to the pH Boost saga. The owners just don’t have a deep understanding of their product.

The plea that “ our product does not contain formaldehyde” was also used by hair care product vendors that sold formulations using paraformaldyde. When the products were heated in the course of the hair treatment, formaldehyde fumes were given off.

 

[taricha]

Here’s an in vivo study of ammonia and formalin.

https://fish.ku.ac.th/pdf/Bulletin29-38/Fishery Bulletin no 32-1-2.pdf

So the mechanism I proposed is viable, albeit at much higher doses of formaldehyde than those suggested by our products. By my calculations, taking the paper at face value, the neutralization of 0.12 mM NH3 would require about 3 mM formaldehyde.

That catfish /shrimp formalin paper concluded that formaldehyde + ammonia was toxic, and assumed that it was because the formaldehyde formed a product with ammonia.
They did not however compare it to the toxicity of just that level of ammonia or that level of formaldehyde over the same time period - so it could have just been the toxicity of unreacted ammonia or formaldehyde over the long time period.
They also did not demonstrate that any product was actually formed between formaldehyde and ammonia, they simply used a total ammonia test (which formaldehyde breaks... we'll talk about that in part 6) and when the formaldehyde caused it to read zero ammonia, they concluded that was the right amount of formalin to use.

 

[taricha]

FWIW, Seachem makes this very strong claim:

https://forum.seachem.com/forum/general-discussion/1708-prime
"Prime does not contain any formaldehyde. It is a proprietary aqueous solution of complexed hydrosulfite salts. I hope this helps!"

I'll take the position that may not be a strong claim?
hydroxymethanesulfinate is not formaldehyde. Neither is rongalite. A bottle can contain HMS and rongalite and not contain formaldehyde. Over time, under aquarium conditions, small amounts of formaldehyde would be released from those compounds, but they aren't literally formaldehyde.

alternately, the Tetra rongalite patent indicates that you play the same game with other aldehydes if you really want to say you don't use formaldehyde

(chemical test methods for formaldehyde would also detect other aldehydes similarly)

 

[taricha]

So here's some data I have that's responsive to the hypothesis that these ammonia remover products could form formaldehyde-ammonia combinations that then pass through the membranes and fool the NH3 films.

I took smaller beakers of tank water and placed them inside larger beakers of tank water that had been spiked with ammonia, and treated with nothing, ClorAm-X, or Prime.
I left them sealed and inside an insulated container for a number of hours, and then measured the amount of ammonia that had diffused out of the spiked tank water through the air and into the inner small beaker of tank water using a total ammonia test.

Run 1 measured at 12 hr

The amount of ammonia diffused through the air into the inner beaker (y-axis) was proportional to the ammonia concentration in the outer beaker (x-axis), and treating with recommended doses of Prime and ClorAm-X did not change that diffusion rate to any significant degree.


This was run 2, measured at 12 and 36hr - with the same result.

If the chemical compounds suggested earlier had been formed to a significant degree then we would expect a much lower rate of diffusion of NH3 into the air, and thus slower to get into the inner clean beaker.

They would diffuse into air much more slowly than NH3.

The above data indicates no such effect.

 

[taricha]

Also wondering about the half-life of formaldehyde in aquarium water. Maybe @taricha has that data.

I've got a paper on that, somewhere....

 

[Formulator]

So here's some data I have that's responsive to the hypothesis that these ammonia remover products could form formaldehyde-ammonia combinations that then pass through the membranes and fool the NH3 films.

I took smaller beakers of tank water and placed them inside larger beakers of tank water that had been spiked with ammonia, and treated with nothing, ClorAm-X, or Prime.
I left them sealed and inside an insulated container for a number of hours, and then measured the amount of ammonia that had diffused out of the spiked tank water through the air and into the inner small beaker of tank water using a total ammonia test.

Run 1 measured at 12 hr

The amount of ammonia diffused through the air into the inner beaker (y-axis) was proportional to the ammonia concentration in the outer beaker (x-axis), and treating with recommended doses of Prime and ClorAm-X did not change that diffusion rate to any significant degree.


This was run 2, measured at 12 and 36hr - with the same result.

If the chemical compounds suggested earlier had been formed to a significant degree then we would expect a much lower rate of diffusion of NH3 into the air, and thus slower to get into the inner clean beaker.


The above data indicates no such effect.

Clever experiment! Fairly conclusive too.

 

[Formulator]

So, the more data you share, the more I am being convinced that these products really are just bologna. Now my question is how can they get away with this and who is going to hold them accountable? This sounds like the making of a pretty massive class-action lawsuit to me…

 

[Randy Holmes-Farley]

I'll take the position that may not be a strong claim?
hydroxymethanesulfinate is not formaldehyde. Neither is rongalite. A bottle can contain HMS and rongalite and not contain formaldehyde. Over time, under aquarium conditions, small amounts of formaldehyde would be released from those compounds, but they aren't literally formaldehyde.

alternately, the Tetra rongalite patent indicates that you play the same game with other aldehydes if you really want to say you don't use formaldehyde

(chemical test methods for formaldehyde would also detect other aldehydes similarly)

I was referring to the fact that these compounds will naturally be decomposing as they sit in the bottle. The claimed decomposition products of rongolite and hydroxymethanesulfonate contain formaldehyde.

https://www.researchgate.net/figure...dic or heated,can still derive sulfur dioxide.

"Under acidic or heated condition, rongalite will generate formaldehyde and sodium hydrogen sulfite, and then sodium hydrogen sulfite can still derive sulfur dioxide. "

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/JD091iD02p02801

"The rate constant of HMSA decomposition to form formaldehyde (HCHO) and aqueous sulfur dioxide S(IV) at pH 4 and 5 was 4.8 ± 0.4 × 10−7 and 3.5 ± 0.2 × 10−6 s−1,"

 

[Formulator]

rongalite will generate formaldehyde and sodium hydrogen sulfite

And based on the smell of prime, I think its safe to assume this decomposition is occurring at least to some extent…

 

[taricha]

I was referring to the fact that these compounds will naturally be decomposing as they sit in the bottle. The claimed decomposition products of rongolite and hydroxymethanesulfonate contain formaldehyde.

Thanks, I get you clearly now.

One thing I'm wondering...if all these products have the same ingredients why do only the Seachem versions have a reputation for stinking?

do you mean figuratively, "not very good" or literal odor?

 

[Randy Holmes-Farley]

So here's some data I have that's responsive to the hypothesis that these ammonia remover products could form formaldehyde-ammonia combinations that then pass through the membranes and fool the NH3 films.

I took smaller beakers of tank water and placed them inside larger beakers of tank water that had been spiked with ammonia, and treated with nothing, ClorAm-X, or Prime.
I left them sealed and inside an insulated container for a number of hours, and then measured the amount of ammonia that had diffused out of the spiked tank water through the air and into the inner small beaker of tank water using a total ammonia test.

Run 1 measured at 12 hr

The amount of ammonia diffused through the air into the inner beaker (y-axis) was proportional to the ammonia concentration in the outer beaker (x-axis), and treating with recommended doses of Prime and ClorAm-X did not change that diffusion rate to any significant degree.


This was run 2, measured at 12 and 36hr - with the same result.

If the chemical compounds suggested earlier had been formed to a significant degree then we would expect a much lower rate of diffusion of NH3 into the air, and thus slower to get into the inner clean beaker.


The above data indicates no such effect.

Yes, anything that lowered the concentration of NH3 in the water will lower the concentration of ammonia in the air and thus the rate of transfer of ammonia. Like some earlier experiments you did with the Seachem disks in air, IIRC, this too is a convincing experiment.

 

[Malcontent]

do you mean figuratively, "not very good" or literal odor?

Literally. People are always complaining about the smell of Prime.

 

[LordJoshaeus]

Here's a related question worth testing at some point...there is a filter pad called poly filter that claims to remove ammonia, among other things. It would be interesting to test if it actually does...I've been using it when bagging fish in an attempt to reduce ammonia levels in the bagging water and I am intrigued to know whether that actually helps.

 

[Formulator]

Here's a related question worth testing at some point...there is a filter pad called poly filter that claims to remove ammonia, among other things. It would be interesting to test if it actually does...I've been using it when bagging fish in an attempt to reduce ammonia levels in the bagging water and I am intrigued to know whether that actually helps.

Should be fairly easy to test. I suspect adsorptive mechanisms like that would be more successful than the chemical detoxification methods being discussed.

 

[Malcontent]

Here's a related question worth testing at some point...there is a filter pad called poly filter that claims to remove ammonia, among other things. It would be interesting to test if it actually does...I've been using it when bagging fish in an attempt to reduce ammonia levels in the bagging water and I am intrigued to know whether that actually helps.

The paper mentioned earlier tested them.

If you''re shipping freshwater fish you can use clinoptilolite.