Flourite Dark™ is a specially fracted, stable porous clay gravel for the natural planted aquarium. Its appearance is best suited to planted aquaria, but may be used in any aquarium environment. Flourite Dark™ is most effective when used alone as an integral substrate bed, but it may be mixed with other gravels. Gravel modifiers such as laterite are not necessary. Flourite Dark™ is not chemically coated or treated and will not alter the pH of the water. Although pre-washed, it may be rinsed before use to remove residual dust. Dust can also be minimized by filling aquarium slowly and dispersing water so that the Flourite Dark™ bed is not disturbed. Slight initial cloudiness is normal and will clear rapidly (2–12 hours). To shorten the cloudiness period use Clarity™ in conjuction with mechanical filtration (such as filter floss).