HI 772 faulty or reagent?

[tmccaff]

I tested my alk with the HI 772 and reads 7.0; my salifert reads 8.5 and my KH Carer reads 8.52. The reagent is brand new just opened. Do you think checker is no good? or faulty reagent?

 

[Randy Holmes-Farley Verified Community Expert]

Maybe none of them are accurate. No way to know from 3 test results.

 

[tmccaff]

@Randy Holmes-Farley What you suggest?

 

[Randy Holmes-Farley Verified Community Expert]

I recommend a diy instead of commercial alk tests, but all of these values are fine and if you just pick one device and maintain at this level, all will be well unless all of them are way off (which is unlikely).

https://www.reefedition.com/a-diy-alkalinity-test-by-randy-holmes-farley/