al�um 1(lm)
n.
Any of various double sulfates of a trivalent metal such as aluminum, chromium, or iron and a univalent metal such as potassium or sodium, especially aluminum potassium sulfate, AlK(SO4)2�12H2O, widely used in industry as clarifiers, hardeners, and purifiers and medicinally as topical astringents and styptics.
DONT use copper sulphate. The aerator is not causing the muddiness, but may be helping keep it suspended, if it is causing a rapid enough circulation of the water. If you are going to use chemicals...follow the directions. Use 1/2 part hydrated lime for every part of alum to prevent excessively lowering the ph of the pond. Let the aerator get it circulated good, then turn it off so that the solid particles can precipitate.
