What is up with all this hype of people wanting a clear pool. The river by my house has bits of algae in it that I swim in all the time and have had no ill effects. I think it is about time someone starts to make green liners and we just swim with the algae....if it gets thick enough you can always harvest it and have a salad, right. Plus it would be a huge cost savings. I think this is one of my better ideas, time for me to open my own pool store with a new business plan. Who can I sign up for a green liner, first 10 customers get a free phos treatment.