I live in the Kansas City area, and we had an unusually strong storm last week with tons of hail and about 3 inches of rain. With the ground still frozen, most of the rain ran off the ground and a great deal of it found it's way into the pool (16x32 vinyl liner, 20k gallons), underneath my solid cover.

The water is no longer pristine; I can still see the bottom in the shallow end, but not the deep end.

I'm not sure how to deal with this, so I am asking for input:

1. Since I don't normally open the pool until early May, do I need to start filtering now and can I do that with the cover still on?

2. Is it necessary to vacuum now, or as long as I can keep the water in balance, can that wait until I open the pool (there does not appear to be much sediment that I can see in the shallow end)?

3. The water temperature is currently 38 degrees F, but when the early spring sun hits the cover, the water temperature can rise quickly, and I fear that algae will take hold if I don't do something - will shocking the pool and then maintaining balanced water hold me until I am ready to open the pool?

4. If I don't run the filter, can I add chlorine directly to the pool and let normal dispersion take care of circulating the chlorine?

I tested the water today with the following results:

FC 2
CC 0
TC 2
Ph 7.2
Alk 80
Cya 55

I realize that the chlorine level is too low and I am thinking I need to shock it, but I have never done that without the aid of a filter.

Thanks to all for your suggestions.