https://bigfootforums.com/topic/70965-missing-411/page/30/?tab=comments#comment-1101660
A recent post in the Missing 411 thread precipitated this thread. It involves the drinking of water while out in the field. Cyanobacteria or toxic-algae bloom is something I was unaware until a few years ago. I'm not saying that is the cause in this case but it is something all of us who endeavor into the backcountry should be aware. We should be mindful of the color of any water we hope to filter then drink. It's a topic that's been discussed at both whiteblaze.net and backpackinglight.com.
https://www.whiteblaze.net/forum/showthread.php/139665-Water-purification-when-a-Sawyer-is-not-enough
https://backpackinglight.com/forums/topic/83342/
There is a lot of moving water where I go although in the dog days of summer some creeks will dry up. If I lived in areas where cyanobacteria warnings were in place, or have historically occurred, I'd carry as much drinking water as possible rather then rely on filtering. Having said that, I'm considering getting the Sawyer S3.