The ammonia, nitrate and nitrite tests have to be left for 5 minutes after addition of the reagents, pH is immediate. I use these tests and it does stress that when doing nitrate the 2nd reagent needs to vigorously shaken for 30 seconds prior to addition, and then the sample tube needs the same vigorous shaking for a further minute, before leaving to develop for 5 minutes
I lost the book in do
ors some were and found it last nite. and read I last nite and found I was donig a nitrite test worng and my water has been fine what plonker I have been lol and all them water changes I have been doning oh well .