Obtain potassium permanganate to kill the moss. This option is best for those with light to moderate moss growth. Potassium permanganate is available at most pond supply stores and some animal feed stores. When used properly, the product will not kill your fish or nearby waterfowl.
Calculate the acre-feet of your pond by multiplying the pond's surface acres by its average depth. For example, if your pond covers half an acre and has an average depth of five feet, its acre-feet is 2.5.
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