I have about a .5 acre pond that is pretty murky. <6" visibility. It doesn't seem to have any vegetation in it. Im fixing to gather a sample in a jar and let it sit.

Question is, how much of a negative impact does it have on fish. Im thinking about making it a holding tank for large CNBG. Probably will do a little supplemental feeding but nothing big.

I don't really want to spend a bunch of money on Alum/liming as this is not going to be my main forage pond.

Ok hold on, I have see something 12" down so my visibility is more like 12". My bad. I took a sample in a jar. I'll see if I get anything to settle in the bottom.

Also another interesting observation. The mudd along the edge that I could see in the water almost looked like Coral. It had tons of what appeared to be 1/8-3/16" diameter holes all in it. tons of them.

Muddy water inhibits the growth of plankton by not allowing light to penetrate and therefore reduces the amount of food at the base of the foodchain. It also makes it more difficult for fish to find food and decreases the amount of oxygen produced through photosynthesis pond.

You may want to do a search on secchi disks for measuring clarity.