I am so jealous of all these gorgeous ponds! Every time we have tried to do a natural pond, we always struggle with filtration other than on the farm where we had huge ponds. Even now, I drain and refill our mini-ponds daily (having drains in them has made it so much easier), but good Lord all the water. I am going to try to set up something where the drain pipe drains into a big bucket of gravel or something that might help filter some, so it doesn't pool as much. Has anyone tried something like this? I thought about trying to find something like charcoal as well to see if that helps neutralize it a little (although right now, we are not having much problem at all with smell or anything).