Dave sounds as though some folks are completing application of A and B with a final dose of sodium bentonite. The bentonite apparently helps encourage the linear and crosslink polymer to sink immediately in case there's some wind/current which causes them to drift. This is a new application suggestion from Aquaben which first was introduced by them a couple months ago. Apparently they are still learning, too.

FWIW I have never used the bentonite step in my treatments, and still achieved good results. I think it's more of a insurance measure than anything else - if it's cheap and available, might as well implement this step.

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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