Hannah instrument checkers... unreacted sample?

[sikemd]

I have a few of these checkers that I've been using. I am confused as to what an "unreacted" sample is though. Does it mean an unreacted sample of tank water, or RO water? I've been using tank water and I'm not sure if this is correct. Can anyone clarify?

 

[sikemd]

Nevermind I think I found my answer. Searching around I read some posts saying to use the same sample glass for both unreacted sample and reacted sample, due to the way the checker works with light, and that slight variations on the glass can cause inaccurate results.

 

[sikemd]

I now have another question though regarding the checker, haha... Does anyone know if the unreacted sample part has to be done everytime, or just every so often?

 

[twilliard]

I now have another question though regarding the checker, haha... Does anyone know if the unreacted sample part has to be done everytime, or just every so often?

Every time

 

[Elementalj]

Every time

Beat me to it. [emoji6]