First of all I think I have all the info posted in my signature that you need. If not LMK. We purchased our pool last year and the guys at the store SOLD us on Pristine blue. Had a great season last year with it and beautiful water all year. However went to open our pool this year with nasty green water. I got the pump running good followed the instructions in our manual and no change in the first two weeks. So I took a water sample in and they told us what all to ad. Done as they said...week later very small to no change at all. I then do some research on Pristine Blue and decide...Hum thats not for me and not very uncommon. So I go back one last time. They tell me to add 9lbs of some sort of calcium into a pillow case and let it slowly disolve into the pool. Told me that would help out....Still no change. I then go back and tell them hey guys this is not working I want to switch over to chlorine what do i need to do. I get chlorine tablets, shock, and some kind of strong algecide and do as they told me. Well the pool water is better cholored but now 3 days later their are lots of stuff floating through the pool. Looks like small little white particles and right in the middle of the pool it looks brownish...Im close to giving up here. Would it be better to drain the water out and start fresh or what??? Im open to any and all sugguestions here. I figured I would need to change the sand in my filter but the guy told me it should be fine and assured me that the shock, chlorine and algacide would take care of my problem...$300 and 3-4 weeks later still in the same boat...