Hanna N and P checker instructions

[RobertK]

I have the Hanna Nitrate HR and Phosphate ULR checkers. I noticed in the nitrate instructions its says that after adding the reagent to the cuvette to "shake vigorously for 2 minutes" but in the phosphate instructions to "shake gently for about 2 minutes". I shake them both the same way. I would describe my shaking technique as slightly more vigorous than gentle but more gentle than vigorous shaking. Seriously, does this make any difference? The reagent dissolves and there no bubbles visible in the cuvette when I place it in the checker, isn't that all that matters?

 

[Randy Holmes-Farley Verified Community Expert]

Dissolved reagents and lack of bubbles when the timer runs out are, as you note, the reasons for shaking and setting. If that is happening you are mixing reasonably.

 

[Euphyllia098]

I mix for like 30 seconds tested, then another sample for 2 minutes. The result was the same.

As long as the reagent is dissolved I don't think it makes much difference.