15 pounds of black seiryu stone this beautiful unique stone is sure to bring out the true foundation of your aquarium with the beautiful Gotham like looks and structure These stones are shaped into it is sure to give that extra natural effect to your tank pretty much like you have stones from a mountain especially when your aquarium really highlights the chops and white veins that run along it's curved not only that your fish will love it! these stones they can also be used in terrariums planters and more!