The wild card for the clear water thing is how far down is the murk? I've seen the trolling motor bring it up and even sometimes a caught fish will bring a little up. I'm with PPG in that the smell factor is big. Went swimming with family in Lake Arthur the other day and standing in the boat I could see to their waste in 5' of water. After walking around the murk was coming to the top, but of course their feet were doing it. The real test for good water is that the fish bite.