Quote Originally Posted by waterbear
I don't believe an excess of the reagent is going to cause off results since the precipitaton is going to be in the reaction with the CYA in the water and once it has all reacted then an excess of reagent should not cause any problems. I could be wrong on this but I don't think so. The correct mix is equal parts of each.
I'd agree with you, if it weren't for the fact that when the poster used the marks, the CYA was 50, and when she used equal parts, the CYA was 30. That shows me that it would make a difference! Thanks for clearing it up. I'll make sure to use a 50/50 solution. Actually I'm going to try it both ways and see if I get different readings.