Gypsum did not work on the jar test, but a pinch of alum powder did, and cleared the jug of water in less than an hour. I only have a very small jar of medicinal alum. I need about 20 pounds of it to clear my sediment pond. Where could I get 20 pounds of powdered alum at a reasonable price? I aim to mix it with 10 pounds of quicklime in a tub and apply the slurry with a hose with a nozzle connected to a small water pump.
Last edited by John Fitzgerald; 04/20/20 02:32 PM.
