Sorry, I've been gone for a few days, where are we on this???wasabi said:
Just as a note, then pH is this low and still cycles on a daily basis, and the meter error has been ruled out, it is almost ALWAYS a problem with excess CO2. I would get a Pinpoint controller and connect the solenoid for the Calcium/CO2 reactor to the controller. This will save you a little effort with the kalkreactor, (which I would recommend anyway) and still give you a reasonable level of Ca and Alk. The summer and deep winter for most folks coincides with a similar occurance, as the house gets shut up and CO2 accumulates in the in-house environment. The above suggestion to pipe in outside air for the skimmer is one of the ways to fix this.
Post and let us know where you are on this.
HTH