Getting ready to close the pool in a couple of weeks and I'm starting to get things in order for the close. I've had recurring algae issues and kept my FC level at the high end now for awhile, (9ppm). Water has been crystal clear and since switching over to the BBB way of doing business have been very happy with the clarity of the water, except for the algae. 2 types--Wall clinging green & yellowish/greenish bird-like droppings. Not horrible but fairly constant. Have gotten a pretty good beat-down by it this year and was looking forward to closing as the summer was crappy also. So I go to pull the ladder and carry it to the driveway and was shocked and amazed at the green crud that started to come out of all the nooks and crannies of it. The ladder was LOADED with green swamp water! It's your standard white plastic above-ground pool ladder, with numerous weep holes in it, to harbor algae! OMG! No wonder I've had such a time brushing, shocking and more brushing. I would always brush the ladder whenever I brushed the pool as the ladder would have a light green film on it. Now I know why. I've often wondered if the ladder was the culprit and now have disgusting visual proof. Right before switching over to the BBB method I let the chlorine level drop to zero. My fault. I'm thinking that was the springboard for my summer struggle. Now I'm in the market for a new ladder. The particular design of this one in my mind is one that I won't choose in the future, but I guess one could say that in a properly sanitized pool that this would never happen! I'm hoping that in the couple of remaining weeks that the pool will remain open, I'll see a marked decline in my current algae situation.