Alum treatment can help bind and sink Phosphorous and improve problematic planktonic algae blooms by rendering it unavailable. Seek a pond management professional in your region - David Beasley is a good choice and I believe his company is listed in the resource guide [www.solitudelakemanagement.com]. David is a great guy and good friend of mine - you'll be in very capable hands.

IIRC there was a recreational lake in Fremont NE that was closed for several weeks over a few seasons due to toxic blue green algae blooms. It was treated with Alum and believe it was successful. Alum treatments can lower your PH levels and cause fish kills, so adding lime to buffer the swing is sometimes necessary. Again, best left to a pond management professional. Here's the article on the NE alum treatment - hope it helps:

http://water.epa.gov/lawsregs/lawsguidance/cwa/tmdl/nebraska.cfm

Many men go fishing all of their lives without knowing that it is not fish they are after. ~ Henry David Thoreau

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