SeaChem Flourite 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 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 is not chemically coated or treated and will not alter the pH of the water. Although pre-washed, it should be rinsed before use to remove residual dust. Dust can also be minimized by filling the tank slowly and dispersing water so that the Flourite bed is not disturbed.Slight initial cloudiness is normal and will clear rapidly (2-12 hours). This bag is sufficient for about a 5 cm (2 inch) deep bed in a typical 40 L (10 gallon) tank.Recommended use is 1 kg (2 lbs) for approximately each 200 cm2 (31 in2) of tank bottom at a depth of 5 cm (2 in).