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Waterfall Worms

Subject: Waterfall Worms
by Anonymous on 14/8/2011 20:11:38

Sorry I can't supply any pictures, but can anybody identify the creatures living on my pond waterfall? I built it myself with huge rocks, and the pond has been established for about five years. There are small black worms about 6-8mm long in layers about 2mm thick in all the parts of the waterfall that are constantly wet, but not directly under the strongest part of the flow. They are also in the waterfall outlet pipe.

Any help would be much appreciated!