I've heard of people attaching them to a milk crate to keep them up off of the bottom, and I've a single diffuser attached to a 2' x 3' piece of plastic sheet that was roughly 3/16" to 1/4" thick to help stop the mud from getting stirred up.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).