Aquarium gravel with precise grading to permit free flow of nutrients and oxygen to nitrifying bacteria. Keeps water clear. Resists packing channeling and anaerobic dead spots beneath decor.

Don't settle for an ordinary gravel. Natural dramatic colors and textures combined with pH support characterize our CaribSea Coraline Aquarium Gravel products. These are coarser materials suitable for most undergravel filtration and fish systems or as an accent for finer sands anywhere where elevated pH values are desirable. Consider the Coraline products in brackish or Cichlid aquariums (Central American or African). Our substrates are purposely engineered and free of impurities such as ash, metals, pesticides, and silica which allows you to create a safe and beautiful environment for your fish and invertebrates. Precision grading makes system design a breeze!

Rinse a few pounds at a time in a plastic bucket until overflow turns from a milky to cloudy appearance. Any remaining cloudiness will disappear after a few hours of pump operation.