I had very muddy water until I got good ground cover established throughout my watershed. Waterways, ditches, and banks to the waterline all can contribute to suspended clay.
Jar test is collecting a jar of pond water and setting it undisturbed for a couple weeks in a dark spot. Taking a picture every few days to see if it clears and what settles out. Best to take in same lighting conditions every time and be careful moving jar so you don't agitate settled gunk.
