I would like some opinions on what to use. So far I have just used the carpet, but it is old and rotting out on me. Time for a replacement. Somebody told me the moss tends to load up and can be difficult to recover all the fines from. On the other side, I was looking at carpet at Lowes and a fella there showed me what several customers had purchased for their sluices. It was finer on the ridge pattern than what I was using. Any input?