I recently fired my pool man, as I had a hard time believing him. He claimed that, because my pool was replastered twice, that caused the sand to get clogged up and I need to replace the sand. Actually, he said I needed to replace my entire filter (five years old). Then he said my laterals are probably broken. Then he said I would need to replace my backwash valve (fixed with a couple of O rings).
So, I've decided to take matters into my own hands. I guess my first question is, should I replace the sand? Having read a number of posts here, it seems to me that green water is a chemistry problem, not a sand problem. What are the odds that the sand is the source of my green water?