saving calibration solution

[starramus]

frugal is my middle name so I am saving my 6.86 pH meter calibration solution in a sealed bottle. Has anyone tried this? Since evaporation would change the concentration I have placed a cap on the plastic bottle. Is this feasible, or am I just too fricken cheap?

[Potted]

I use a shot glass 1/2 full to cal. Mine, I don’t mind waisting that much. I keep the rest in its original bottle.

[starramus]

I am using the powder, and the instructions are to mix it with 250 ml of distilled water. I hate to throw it all away so have come up with this solution.

[Guest]

I use the powder too and was wondering the same thing lol.

[BearsFan]

I jarred my 6.86 and my 4.0 in a couple of mason jars, it seems to be fine but I have only calibrated once with them so far. Same idea over here of being a little cheap, ha!

[gbauto]

Using the same calibration powders in glass flip-top jars. They have been in use for 6 months and I don't see any drift.