Hannak alk checker acting weird

[DrewBrees713]

I’ve been testing my nano for the last 5 days i didnt add anything alk or cal and here are the numbers. Please advise.
Mon 8.8
Tues 8.9
Wedn 8.8
Thurs 8.4
Tested today twice minutes apart 8.8 &8.6.

 

[Jshiloh]

Mine has been weird also. Tested my 120 this past Monday and it said it was at 6.9 then 6.6 an hr later. Replaced the reagent with a new one on Tuesday and then alk was 6.9, I manually dosed 15ml to try to raise it some, tested again an hr later and it said it was at 6.7. I picked up a brand new trusty salifert kit and alk was at 7.2 then 7.1 this afternoon. Think I’ll stick with salifert for now on.

 

[JimFuller]

Those reading appear the be with in the error range of the test and checker. I do not see an issue.

 

[watdachuck]

Also, make it a standard practice to wipe the exterior of the vile with a soft lint free cloth each time you handle it before each part of the test.

Any smudges or fingerprints can have an effect on the reading.

 

[DrewBrees713]

I think i have it figured out. You’d to get the water as close as the water line as possible. Ever so slightly less or more will render a different value.