ofcourse you can put ribbed rubber mat into your sluice. it can be bought at most home repair (Lowes/Home DePot/ETC) BUT you need to watch the shape , size of the ribs.. and using ribbed matting requires you to screen anything you run through it prior to using it...now this would be considered a cleanup setup to be used after running your material and then reconfigureing the sluice with your ribbed matting. I made a sluice that was 3 1/2 foot wide and 3 ft 9 in. long it had a inclined 3/16 trough that had a large hopper at its headend that I shoveled into. the spray bars kept the material moveing on the trough and the sluice that had only black ribbed rubber matting and the water pressure was kept low to prevent the fine gold from being washed out.I had valves on everything to control the flow where I wanted it. for fine gold recovery , you need to slow everything down to let it drop out and get trapped. It worked !