hanna test kit

[jose hernandez]

so ive been testing my hanna alk test kit to compare it with my trident results and they are way off so i decided to get a new bottle of the hanna reagent to compare it and the old bottle is reading 8.1 as opposed to the new bottle is reading 8.7 trident 8.68 old hanna expires sep 2021 new bottle dec 2022 is this normal?

 

[lapin]

Yes
I always compare old to new so I know what the difference in bottles is.
Evaporation and Settling in the old bottle I think can cause the difference.
I also have the STD test vials just to be sure my hanna is not the issue

 

[jose hernandez]

They should at least tell us if the test won’t be as precise long term