Understanding test kit chemistry

[TomK2]

Ok, I have tried hard to find explanations of what EXACTLY happens when the little drops go into the test tube. I have discovered bits and pieces here and there, such as that extremely high nitrite and carbonate levels can affect the ammonia reading on a salicylate test, amquel can totally ruin a nessler test, and so on. I have not been able to find out if Chloramine shows up on a nessler or a salicylate test without first dechlorinating. Why do I want to know? well.... I just do.

Does anyone know of a comprehensive source that explains in depth how the test kits work? What the pitfalls are? things to avoid? If I could find a book on this maybe I would be asleep now instead of reading posts on AA!

[BrianNY]

Hey Tom...............great website

I suppose you could try emailing both Wardleys and Aquarium Pharm. I'd imagine they both have websites.

[xray]

Here's the site to e-mail Aquarium Pharmaceuticals. Your way over my head on this one. But Hey let us know what you find out.

http://www.aquariumpharm.com/contactapi.html
HTH

[TomK2]

well, it wasn't easy! I searched with my isp search engine and yahoo and google and got nothing. I even stopped by the local library and browsed through the chemistry section and could find out nothing about ammonia water test kits. Then a last ditch "askgeeves.com" search eventually got me through a couple of links that DID have the answer!

And the answer is.....

Salicylate testing for ammonia
This analytical method is based upon the treatment of ammonia compounds in a seawater sample with chlorine to produce monochloramine. The monochloramine is reacted with salicylate to form 5-aminosalicylate. Sodium nitroprusside acts as a catalyst for the oxidiation of 5-aminosalicylate to indosalicylate, a blue colored compound. The blue color is masked by the yellow color from excess reagent to give a final color of green. This color change is proportional to the amount of ammonia in the sample and can be determined spectrophotometrically

Sooo…..if you have chloramines instead of ammonia, it should turn color and detect the chloramines! Thus, a positive ammonia level from the tap using the salicylate method is chloramine.

Now, unless your tap water has ammonia in it, and I hope it doesn't, wouldn't that mean that the slicylate ammonia test can be used as a test for chloramines instead of buying a seperate free chlorine and total chlorine test?

[TomK2]

Thanks Xray. I actually did email API. Wonder what they will have to say.

[tetrin]

well tom...u have ur facts right ...
monochloramine(NH2Cl) is the dominant forms in water with ph >7 ...which is the case for most water from household taps...so the salicylate test should be able to detect monochloramine...
but below ph 7 dichloramine (NHCl2) is the dominant form, which may or may not form 5-aminosalicylate...i am not sure about this...

good job btw...

[amosf]

Hey tom, look out. I think your avatar is overfeeding that fish!!!

[TomK2]

Hey tom, look out. I think your avatar is overfeeding that fish!!!

Nah, he is just desperate, as I am, to get a biofilter going! 30 days and no ammonia, no nitrites, and no nitrates in a 55 gal with 6 danios and 7 platies. If I don't see some nitrates soon I am going to add more fish.

so the salicylate test should be able to detect monochloramine

I wonder why the municiple water testers use harder tests for chlorine, unless they think it is possible to have ammonia in the pipes. I bet old, used up chloramine degrades to ammonia, so they have to use a different test to make sure that isn't happening. My local water report says no chloramines, and I can't detect ammonia with a slicylate test, so I think I am safe to aerate my water and use it for top offs and water changes.

[TomK2]

Hate to bump an old,worn out thread to the top again, but I finally found some explanations for test kit chemistry, I think. Aquarium Pharmaceuticals didn't give up any information, but other sources did. You can check it out here:

http://home.comcast.net/~tomstank/to...s/page0018.htm

[frog girl]

Tom looks like you got your answers. Having used HACH test kits for lab & field testing I am pretty sure you could save some time by checking out their website or e-mailing them (haven't done it myself but it might help if there is a next time).

[ChileRelleno]

Learn something new everyday!
Thank you, for sharing your research, "Knowledge is Power!".

[TomK2]

Originally Posted by frog girl

Tom looks like you got your answers. Having used HACH test kits for lab & field testing I am pretty sure you could save some time by checking out their website or e-mailing them (haven't done it myself but it might help if there is a next time).

I did check out the HACH website, and the online info section. It was very helpful. Helpful enough that I actually bought their "Water Analysis Handbook", it was about a dollar, with about $8 S&H. It was rather thick! For the article linked above, I relied exclusively on the HACH handbook for explanations of the nitrogen tests, and then read through the Aquarium Pharmaceuticals MSDS sheets that I could find online ,looking for common ingredients. I figured that if AP had the same color indicator, and some of the same ingredients, it would be the same test as HACH, but modified for home use. The water conditioner info came from the manufacturers websites. It took a little bit of work and digging, but I don't feel so mystified by the tests anymore.

edit: Here's the link again, if you are interested
http://home.comcast.net/~tomstank/to...s/page0018.htm