Closing the pool in the next couple of weeks. Water temperature is approaching 60 degrees. Leaves from tall oakes near the pool have just began to fall. I'm holding off closing long as possible. Last year's opening was to a green monster but chlorine,brushing,and a good test kit took care of that in approx. one week. During the winter I drain water from pool a few times. When I drain with sump pump would it be advisable to test and add some 12.5% chlorine or 6% in front of the sump pump with the drain hose circulating water in the pool or am I flirting with fading my liner. Is it better to wait until opening to deal with algae instead of trying to keep in down before late spring opening with chlorine addition every 3 to 4 weeks??? Thanks for the advise!! Done my first opening last year following advise here, went perfect.........

I would definitely add a little bleach if you're pumping off water any way. Since you'll have the pump running it won't hurt your liner as it'll disperse quite rapidly.

thanks bama---- to be clearer,, i'll be pumping with a submersable pump as my main pump will be disconnected and drained. Is it ok to circulate some choroine with this smaller pump.

Yes it's ok to use the sump pump to circulate the bleach.