CARIBSEA ARM Calcium Reactor Media EXTRA Coarse (1 Gallon) Calcium reactors have evolved into several types that require different media sizes. Because of this we now offer ARM™ Coarse for rapid upflow type reactors that have become so popular. This coarse grade of ARM™ will prevent the clogging and upkeep associated with fine media and these reactors.??A high magnesium reactor media. ARM™ Extra Coarse is still a complete reactor media containing not only calcium and carbonate, but essential trace elements as well. Contains: 416000 ppm Calcium, 577000 ppm Carbonate, 3300 ppm Strontium, 1400 ppm Magnesium, 56 ppm Potassium. About 70 pounds per cubic foot 1 gal (00529), 50 lb (00559) Mineral Mud™ Refugium substrate The benefits of mud without the mess – a proven performer Mineral Mud™ – A unique blend of sediments that duplicate tropical fringing coastal mangrove environments. Its particles are in a size range compatible with soft, burrowing infaunal, macro animal assemblages. Ideal for mud refugiums, seagrasses, macro-algaes, and mangroves, Mineral Mud™ provides a variety of trace elements plus calcium, strontium, iron, sulfur and free carbon. In addition, Mineral Mud™ contains live marine bacteria to complete the tropical ecosystem. About 82 pounds per cubic foot. Package Sizes: 1 Gallon Jar, (#00526) Use: Marine and Reef Aquaria Mineral Mud™ Refugium substrate The benefits of mud without the mess – a proven performer Mineral Mud™ – A unique blend of sediments that duplicate tropical fringing coastal mangrove environments. Its particles are in a size range compatible with soft, burrowing infaunal, macro animal assemblages. Ideal for mud refugiums, seagrasses, macro-algaes, and mangroves, Mineral Mud™ provides a variety of trace elements plus calcium, strontium, iron, sulfur and free carbon. In addition, Mineral Mud™ contains live marine bacteria to complete the tropical ecosystem. About 82 pounds per cubic foot. Package Sizes: 1 Gallon Jar, (#00526) Use: Marine and Reef Aquaria