Spectrastone Shallow Creek Regular for Freshwater Aquariums, 5-Pound Bag Go to amazon.com Related posts Best aquarium rocks natural Top 10 best fish aquarium rocks: Which is the best one in 2019? FeatureWill not affect PHSafe for use in freshwater aquariumsNon-Toxic coating DescriptionShallow creek regular natural for freshwater aquariums. Will not affect PH. Safe for use in freshwater aquariums.