Maybe it isn't of any use my advice to slimeysime now, but to other guys may be usefull in the future.
For silty waters the best leads are the Trilobe leads, better if in-line. This leads when enter the water start raise the nose and slow down. So were where a dumpy pear or a flat pear lead starts drilling for oil, the trilobe lead setteles on the lake bed and it gives the fish a chance to see your bait.
The solution with the PVA bag is also good as long as you don't pierce the bag. The air that is traped inside the bag slows it's descend.
Hope it helps, Mihai!