I see the standard recommendation for pools being chlorinated "by hand" - manual additions of some type of liquid chlorine seems to be 50, though I've seen posts here giving that a range of 30-50 depending...
I also see that the recommended level with a salt system is a bit higher than that, 70-80 seems to come up a lot.
That's a pretty big difference - I'm wondering why?
I get that a salt system is a much more continuous process and _should_ maintain a more stable FC value, where a manual process is going to see a spike after the addition and a decline until the next addition. But in practice the salt system only gets run a few hours a day and the result is similarly uneven.
Anybody have a good explanation for the discrepancy?