somethin' dont jive

[Thever]

I did a nitrate test the other day in my planted tank and it read 0. I added some ferts and tested later....still 0. I just made a new fert solution of 1 teaspoon of KNO3 in 110 ml of water, which I then added 2 ml to a 2 liter of water. I tested it and it read 0. ARRRGH! This is the 2nd nitrate test kit that doesnt do what its supposed to.

My plants look bleak as I dont know if my solution is crap or the test kit is. Nice.

Any ideas?


<UPDATE>

I searched around on the web and found some API nitrate instructions. Seems you have to shake the 2nd bottle hard for 30 sec, and then add drops, and then shake the tube hard for a minute. I never saw that in my instruction booklet- and I read it ....twice:butt:

[jsoong]

The 2nd bottle is an emulsion of some sort & if you don't shake well, you don't get a reading. <And if you've done a few test without shaking, then the bottle prob won't be any good, as the concentration of the reagent would be off even if you shake it well the next time...>

I learn that the hard way as well .... after making up a reference solution of KNO3 & finding that the kit was way off.