Bleach in ponds?

[Bubblewrap]

My view is that algae is harmless and it cleans toxins out of the water removing nitrate and ammonia making the water safer to drink. The presence of algea psions the water no more than a cattail would. The dangerous stuff is "blue green algea" which is not algea at all and is instead cyano bacteria. Cyano bacteria should be killed it often clumps together or forms a residue if you break up the clumps and filter them through a paper towl they will reform within 24 hours algea will not.