I was talking to a friend who runs a dog rehab pool. It is indoors. Her pool place recommends she maintain a chlorine level of 1 ppm. A google search indicated a recommended level of 1-2 ppm.
Your site recommends 2-3 ppm (I assume my FC of 5 is the equivalent of 2-3 ppm?)
Why are your recommended levels higher?
How does the FC translate to ppm?