For
most ponds, gypsum application
rates will range from about 1,000
to 2,000 pounds per acre (Fig. 4).
In hard-water ponds (calcium
hardness greater than 50 mg/L),
the water is nearly saturated with
calcium and gypsum may be ineffective.
In that situation, alum will
be the only effective coagulant.
All the coagulants mentioned can
remove phosphorus from water.
As phosphorus is an essential
plant nutrient, it may be necessary
to fertilize the pond after treating
it for turbidity. On occasion, phytoplankton
and clay can mutually
coagulate, so fertilizing to start a
phytoplankton bloom may also
clear water of suspended clay particles.
Lime = better water quality and fertility when needed. Read this.
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