The Architect
Member
What am I missing "... just not distilled." Both RO and distilled remove hardness from the water. The resultant pH should be about the same as the source water. I just tested my RO v my distilled- both pH @ 9.2. I also add ~ 2% H2O2, to keep the probes clean.
Run Neo, run!
DO NOT store your pH electrode in distilled or deionised water as this will cause ions to leach out of the glass membrane and reference electrolyte, causing a slow and sluggish response.