Nature’s Ocean 12inch Coral Base Rocks for Aquarium 40Pound

This natural porous aragonite rock is filled with naturally-formed holes that not only look great in your set-up but help maintain aquarium health by acting as a biological filter. Plus the porous surface is the perfect environment for denitrifying marine bacteria to grow which work to decrease your tanks nitrate levels over time. The unique shape means every rock is one-of-a-kind and also makes it easy to stack when growing live corals or adding to coral-based environments. Plus the rock has been soaked in a deep water well to prevent leaching in your aquarium.