ok well i would try the korda silt coloured rig tubing or if esp do a silt coloured one then even better. u can still use a silt/chod rig using tubing. all i would do is use enough so you have at least 3 feet of tubing along the lakebed. so if the lead is plummetting into the silt say 2 feet then you want 5 feet of tubing if you get where i come from.
dont be afraid to use leadcore though as i have found the stuff to be invaluable and will never use tubing or products alike again.
if you need more help i can make up a diagram for you? so u can see exactly what i mean