Rainman, I have suspended clay. It has been muddy since it was dug almost 2 years ago. I don't have any water coming into my pond, just rain water. I did the gal jug test with different amounts of gypsum and it worked. Doesn't Alum lower PH quite a bit? I want to do whatever works. How much Alum would I need for a pond my size if that is what I need? Thanks
Suspended clay is un bonded silica and nutrients. Most of the time they are of a positive charge because naturally soil is positive.
As Rainman has stated alum will clear up 99% of suspended clay because of how it is a negative particle looking for a positive bond. Giving your water solution the correct charge with out pushing your PH out of wack to much will flock the clay out of the solution. Rainman knows his alum treatment and you should take note of his suggestions.
Sulfur is sulfur how ever you want to add it. Just make sure it is soluble and as fine as your clay particles you want to flock. If not you will have added dirt to the bottom of your pond. Different gypsum has different amounts of sulfur that is soluble. Getting the correct amount could be a crap shoot.
Cheers Don.
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