Well, the pond is nothing more than a fire-prevention plan. It's about 75 x 50', with a depth of about 4'. Pretty small by most standards, but it hold an estimated 50-80k gallons of water. I live in an extremely rural area (nearest volunteer fire department is almost an hour away), and my well-pump driven water source is anemic at 10GPM for a max of about 300 gallons before it runs dry.
I had a local dozer guy dig the pond, using the qualified clay soil - so no liner. There is some dampness on the exterior of the far berm, but water level doesn't drop more than about 1/2" per week (presumably due to do evaporation).
I didn't consider a liner since the confidence on the clay was high. However, I didn't realize that the silt simply doesn't settle over time. As stated, I tried some flocculant - which did work for about 3-4 days - until we had some rain and the run-off collected more clay sediment and returned the water back to the cloudy, muddy look.
Until I can get the edges of the pond erosion proofed (i.e. vegetation, liner with rocks, etc), I think I'm fighting a losing battle.
Wife wants to add koi and other decorative fish, but I don't see much point given the lack of clarity.
The drywall addition peaks my interest. Does that affect the pH of the water, or otherwise put aquatic life at risk?
I've added a crap-ton of river rocks along some of the edge (before thinking about putting a liner beneath it - so if I go that route, I'll have to move every frigging one of them), which I think really increases the esthetics but not the cloudiness. We've also added 4 aerators and some aquatic floating plants - in hopes that this would somehow improve the biology of the pond and help clear it up.
Incidentally, the pond coloring is just dye - specific to ponds. It's not copper-based. It actually has a pretty short life - about 3-6 months depending on sun intensity. I figured if it's too Vegas/Liberachi-ish, it's a self-limiting problem.