I have a Tagelus TA 60 filter with new sand, summer 2013...Pentair HiFlow 6-way valve... and a pump that works well...great filtering and water flow. I have brushed it once a day, and I run the filter through the night (about eight until seven in the morning) Tonight I put in three gallons of bleach. I could see that it was turning from a darker green to an apple green but I cannot keep the chlorine level high enough by adding one gallon of bleach each evening....it does nothing...meanwhile the ph is 8.2, however was at 7.6 until just a few days ago. Help me!!! I cannot go another summer with a swamp!!! I spent at least a thousand dollars last year at the 'pool store' adding everything of this and that...no luck. I am still suspicious that the ex is throwing in a sprinkle of fertilizer...but cannot prove it. PLease tell me what to do next...this is so annoying. Thanks!!!