Coworker was skeptical the other day. Said there was "no way" a pool could be kept clear with "just bleach and a filter". Told him I'd bring pictures, he said if I could take a picture that truly showed a crystal clear pool, he'd give 'this BBB thing" another look.
This is what I'm showing him tomorrow.
Taken with an iPhone from 12+ feet away. That's a half dollar 4' deep.
http://i.imgur.com/9kT4F.jpg for Full Res