Just tested it. Fill water comes out to 125-150. I tested it with both my "old" reagents from last year and the new refill I just got today. I now forget which one was which.. but either way, it's in that ballpark. Granted, I did just get a letter in the mail stating that they're messing with the water and it may smell/taste odd for the next few weeks. I don't know if that's skewing my tests to be lower than average.
We do have an autofill in the form of a Fill-o-Matic. Pump runs 24x7 at low speed. No water treatment at the house (no softener, filter, etc.)
On average, my water level sits about an inch below the overflow drain; there's nothing I can do about this given it's location and the level of the skimmers. So virtually any hard rain causes the pool to overflow. When it rains a lot over the course of a few weeks, I end up going through a lot of CYA and salt to put it back up to where it needs to be. Last spring/summer was very dry with minimal rain, so that might explain the stability I experienced (sorry for not having good PM logs, I just generally don't bother doing it since the results are normally so consistent).
Late last year we did get some appreciable rainfall in a major storm and that storm also killed the sump basin pump that my pool overflow connects to. Over the course of the night, the water level had risen so far in the pool it was maybe an inch from overflowing into the yard. I just opened the backwash valve to get rid of all that water. That had to be a ton of water; even with my VSP running at full speed it took a while to drain that back down to a normal level. Embarrasing as it is, I don't think I've bothered to test CH since then - so it's possible it's been this way for months.
Need to get more consistent with my testing beyond FC and pH, I suppose!
