CaribSea Eco Complete Black Planted Aquarium Substrate-Find Aquarium Rocks and Fish Tank Rock Gravel Online at petco.comWith CaribSea's Eco Complete substrate, you can add vibrancy to your freshwater or saltwater aquarium as well as bring out the color of your plants, fish and other aquatic life. Containing essential nutrients, including iron, calcium, magnesium and sulfur in addition to over 25 other mineral supplements, CaribSea Eco Complete Planted Black Aquarium Substrate is the healthy choice for your aquarium plants and other aquatic life. CaribSea's all-natural formula makes the perfect substrate to not only enhance the look of your aquarium, but to also maintain the health of your live plants and keep them well nourished. Unlike most synthetic aquarium rocks, CaribSea Eco Complete contains a live Heterotrophic Bacteria, which is beneficial for sustaining a healthy aquatic environment as it helps to convert organic waste into a natural plant food. This Eco Complete fish tank rock gravel comes in a range of large and small grain gravel sizes that makes for a porous foundation for plants, which stimulates for healthy root growth and optimal bacterial efficiency. This substrate helps to maintain a healthy aquatic environment as it will not increase pH or water hardness as it is free of any carbonates and nitrates. This beautiful dark substrate creates a stunning contrast, which not only brings out the brilliant colors of your fish and live plants, but also helps to reduce fish stress. Add CaribSea Eco Complete substrate to your aquarium today and watch your plants flourish and your fish thrive.