I'm thinking of setting up a DSB (5") in freshwater. I'm going to use tons of MTS ,plants(Vals) and fish that stir sand. I want it to be deep so the anaerobic bacteria that remove nitrates build up like a Saltwater DSB, but I don't want the pockets of toxic gas that all types of sand stirring critters in Saltwater help disperse. I'm using aragonite 60 lb fine, 30 very coarse in a 60 gal hex, going to stock with rift lake cichlids. Has anyone pulled this off, is it even possible in FW? Anyone know of any other burrowing critter that wouldn't be massacred by the fish? I'd appreciate any info you have.