I use similar products in my freshwater tanks to aid the filters, but There is a BIG difference between 50 gallons and millions of gallons of water. IMHO the odds of increasing microbe activity enough to make any noticable improvement are slim to none. In my tanks it takes 1 tbs per 10 gallons of water, with that measurement it would take 50+ pounds of "powder" for the average 1 acre pond. Seems to me the products are a little misleading.

I'll start treating my wife as good as my dog when she starts retrieving ducks.
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