Quote Originally Posted by Matthias View Post
we need to become a bit more concrete here now

about what differences from measurement to measurement are we talking here?

how many measurements do you take per day?
I take 1 measurement per day. I prime the tube every time there are bubbles in it so I can't tell you the differences from measurement to measurement, day to day, but the only time I let the bubble go it gave a result of 12.4dKH from my usual 7-8dKH. I'll stop priming the tubes now and see how it goes.
Taking more measurements a day could help I guess but at the moment I don't need to as I have few SPS and I would only be wasting reagent. (Shipping of the reagent to my location is expensive ie, €28,91)
Thanks for the suggestions. Hopefully the air bubbles will all make their way out one day so I can get consistent values.

Cheers.