I've cleared my pond into a grey pool like thing following the excellent advice here. Problem is it hasn't gotten any less grey in a few weeks. FC loss is very low and tied to sunlight, CC is 0, and nothing is visible in the pool at all..
Just grey water. Filter can run 24+ hours without an increase in backpressure but backs up very quickly with addition of small amount of DE following instructions on this site. I inherited the pool when I bought this house in December and the previous owners didn't take care of much (11 bullfrogs, 4 wheelbarrows of leaves, diet, and worms can attest). I opened the filter up today and the sand inside looks to be playsand not graded #20 silica to my untrained eye. Can someone confirm with a pic?