I have heard of putting bales of hay in will help with the clarity and add some nutrients to a new pond that might be void of nutrients.
In an old pond I renovated it was chocolate milk brown from the native clay so I put a big loader scoop of some hay/manure mixture that came from an area hay was fed to cattle for quite a while. I imagine it was 90% hay and 10% manure, well composted. My thinking was the hay might help clear up the water and the manure help with an algae bloom. Hard to tell for sure but I think it might be helping. I also limed and added crushed rock around the shore line to stop shore erosion which was also adding to the problem.
Just some thoughts. Some of those with lots more experience than me can say if what I did was a good idea or not. Water is still muddy but it has gotten a little better.
In our big pond we dug new I lined it back with topsoil saved from the excavation and it made all the difference in the world. Our new pond has excellent clarity only limited by the algae level. NRCS had suggested we do that if we wanted clear water as the silt particles (from topsoil) are larger than clay particles and will settle out. The type of clay we have, well some of it does and some does not settle out depending on the particular type of clay hit during the excavation. Old ponds that eventually get enough silt will clear up. Otherwise most local ponds that are relatively new are muddy looking.
Update on clay turbidity: I saw the pond about a week ago and much to my surprise the old pond is now almost as clear as my big pond. It also has a nice green cast to it. A couple warm days took about half the ice cover off and the water looked like maybe 18" vis and light green with algae.
I think the lime, crushed limestone rock on the banks, and the hay/manure did the trick. Or some combination thereof.
