Each spring I decide to try something different next fall to make the Spring start up easier.
One Spring I left the winter cover on until April; I opened to green algae.
The next year I decided to open earlier while the water was still cold enough to prevent algae. My pool is surrounded by pine trees and I spent more time cleaning pine pollen debris out of the pool than I spend cleaning leaves from the pool in the fall.
Last year I poured borax in the pool to prevent algae and decided to balance the pool with the cover on in the Spring. My initial water tests this year were:
Cl = 0
CYA = 0 Using guess strips
pH = 8+
Water temp = 52 to 55 degrees
I will balance the water with muriatic acid and Cl and worry about CYA, TA, salt, & borates later.
So next winter I will consider using bleach during the winter to prevent the CYA to ammonia process.
What level of Cl do you have to maintain during the winter? During the summer I normally maintain 5 ppm. At water temperature below 60 algae should not be much of an issue. If you maintain 1 to 2 ppm of Cl is that sufficient to prevent bacteria?