Julian Sprung, always a fan of refugiums, mangroves, sediments and the associated microfauna, was really excited to show off this new line of substrates for the marine and seagrass aquariums.  The aragonite on the left is live and comes in a very pretty little particle size to be very appealing as an alternative for sand beds.  In addition, the refugium specific product on the right, is optimized for seagrasses and the “muck” area of your setup.  Note that the refugium option is NOT mud, but a special blend of sand perfect for planting and known to absorb phosphates.  These items should be available from your local fish stores in the coming months.