Salicylate testing for ammonia:
This analytical method is based upon the treatment of ammonia compounds in a seawater or freshwater 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 using the indicator card.
Interference: (not a complete list, where interference levels are given they are for the Hach Co test, and might not appy to Aquarium Pharmaceuticals):
Extremely hard water (CaCo3 >1000ppm), and extremely high nitrite (>12ppm) and nitrate(>100ppm) levels can effect the test, as would high Iron, Calcium, Phosphate,Sulfate, Magnesium and Sulfide. Food particles will cause the test to turn green also.
So, if you have monochloramine in your water, it should turn color and detect the monochloramine? I have not seen this written, but it can be inferred. A way of testing your tap water for monochloramine!
Aquarium pharmaceuticals does not list the ingredients to the ammonia test, but many of the above ingredients are on the MSDS for the test. I believe it to be the same.
Nesslers Reagent:
Nesslers Reagent is Mercury Iodide in a Potassium Iodide and Potassium Hydroxide solution.
KI + HgI2 or K2HgI4
In the presence of ammonia (
NH3) Iodide is released which turns the solution brown. If the sample has been treated with Amquel, the Nesslers reagent will turn dark brown, invalidating the test. I believe Nessler tests are a one bottle test, while salicylate tests are two bottle tests.
Nitrite Testing:
Diazotization Method:
Nitrite ions react with sulfanilic acid to from an intermediate diazonium salt. This reacts with chromotropic acid to produce a red-orange complex directly proportional to the amount of nitrite present.
Another method uses the same sulfanilic acid, but instead of chromotropic acid the diazonium salt reacts with 1-naphthylamine sulfonic acid to form a different red-colored solution. This may be what is in the Aquarium Pharmaceuticals kit? Since the Nitrate test has a common pathway with the nitrite test, they may have chosen the second indicator to avoid confusion? (see Nitrate testing below)
Interferences: (not a complete list, where interference levels are given they are for the Hach Co test, and might not appy to Aquarium Pharmaceuticals)
Very high levels of nitrate (>100
ppm) since some of the abundant nitrate will convert to nitrite and register on the test. Ferric Ions, Ferrous Ions, Lead Ions, Mercurous Ions, Cupric ions.
Aquarium Pharmaceuticals does not list the ingredients to the nitrite test on the bottle or the instruction sheet, but sulfanilic acid is listed on the tests MSDS sheet, so I believe they are the same.
BTW- your saltwater nitrate test kit will not be accurate, it will read about twice as high in
FW as it does in
SW, and brackish water is way closer to
FW than
SW, I beleive. The above excerpt is from my webpage onthe topic at:
http://home.comcast.net/~tomstank/tomstank_files/page0018.htm
Hope this helps. I think you need to do
PWC's