Onyx? is a specially fracted porous substrate for the aquarium. Onyx? is suitable for most marine and freshwater environments including reef and planted aquariums. Onyx? is most effective when used alone as an integral substrate bed, but it may be mixed with other gravels or sands. Gravel modifiers are not necessary. Onyx? is not chemically coated or treated but does have a slight buffering capacity.
Although pre-washed, it should be rinsed before use to remove residual dust. 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 10 gallon tank. Recommended use is 1?kg for approximately each 200 cm2 (31 in2) of tank bottom at a depth of 5 cm (2 inches).