I hope I can get some help. my pool had recently turn green and I replaced my DE fileter with a cartridge filter. So, I ran and got the water decent but then all of a sudden it's back to being green. A few days ago I bought 2 lbs out "yellow out" and 4 gallons of chlorine. Ran the filter for 24 hrs and water still green. I also just yesterday cleaned the filters and added 7 bags of pool shock. What else can I do? please help.