Good day everyone. this is about my API test kits. i bought my API saltwater master test kit last January, then i bought my reef master test kit yesterday. i tested my nitrate using both the test kits that are included in each set. the saltwater test kit (which i bought in January) showed a result of 80ppm and the reef master test kit (which i bought yesterday) showed 20ppm. :'(
i tested my newly mixed saltwater and got 0ppm for both the test kits... the problem here is that i do not know which of the two is giving me the precise result. i used the old test tubes and the new ones, still same thing happened. i even exchanged bottle # 1 and #2, same thing happened. well, i do not know if i am shaking the bottle # 2 vigorously enough or what... the reason i bought the reef test kit is to have a kit for the PO4 and calcium and probably save money by purchasing bulk than just one kit. (and i hope these won't have any misleading results just as my nitrate).
i do not know what seems to be wrong... i followed the instructions that the API said on their manual.
hope gurus, and even newbies could put any inputs here...
thank in advance.