Has Stream Cleaner How Can I Keep My Artificial Stream Clean?

How can I keep my artificial stream clean? - has stream cleaner

I have a current between two ponds in my garden, and it is full of mud on the floor while the water is clear, because we have both filters for koi carp. Do you think that the realization of large stones on the ground would be useful, though I tried, only small stones and covered with mud. Please can someone help?