I am building a new pond and I decided to fortify the border with mortar and flat stones. That part is fine. However, after I finished, it rained and washed some cement silt into the water. It was cloudy and then settled into a fine layer of silt. I'm thinking about hooking up my filter and pump with some fine material in it and run it for a few days, stirring up the water every now and then. Then clean the elements. I know I won't get it all out. Besides, soon it'll have organic silt and algea anyway. I can think of no other way besides draining the whole thing and then using a "wetvac". This pond is new. 1,450 gallons. No fish or filter yet. Though I have a filter and 2,000Gph pump.