Hi Elsie!

Welcome back--I remember you from "before"....glad to see you've come back to the forum.

Second question first, if your pool is clear, showing no signs of a problem, and not using any chlorine overnight, and you're diligent about keeping your chlorine up adequately, then you could certainly wait until you get 1 ppm CC before shocking--I don't remember where you live, but in many cases the sun will take care of a 0.5 CC before dusk sets in. Almost all pools will have 0.5 at some time, mine almost always does for an hour or so after the kids get out (sweat, sunscreen, dirt off the toys, etc) but it's usually gone by dark. You mentioned tropical storms--I do ALWAYS shock my pool after a hurricane has blown through, though, or after a several-day rain event, even if the numbers are good, because you just never know what the rain will drop into your pool.

As far as your filtering goes, if your pool is very clean, I wouldn't expect your pressure to rise, and I see no need in backwashing it until the pressure does rise. I would, however, backwash it before closing--you don't want all the "gunk" in there from a whole season having all that time to grow bacteria and other stuff that you'll have to kill off when you reopen.

Janet