PH buffer

[meirion658]

Hi there when I bought my digital ph meter I was given two sets of 4 and 6.89 buffering sachets.

How long can you keep the solution for or are they one time use? Secondly how often do you calibrate a ph meter?

Thanks

 

[Gunge]

I've got no idea! But the two solutions I have are tucked away in sealed containers at the back of the fridge. Yes I realise that if I do use them again I'll have to warm them up to 20C! I've only calibrated mine once - before the first use. I'll do it again if I start getting wildy 'off ' readings. For the types of beer I make I can make the necessary additions to confidently hit a mash pH of 5.2 - 5.5. That'll do for me...