Alum is heavier than water and will sink...it will sink even faster, while providing almost no benefit if broadcast dry.

Alum will help the stirred up mud settle out faster, but only until the alum is washed into deeper areas that won't get agitated.

If fish are present, and depending on the grade slope, the alum get pushed to deeper water pretty quickly (days)

Last edited by Rainman; 04/22/18 08:13 PM.