Seachem Onyx Gravel

Onyx is a specially fracted porous substrate for the aquarium. Onyx is suitable for any marine or freshwater environments and is ideally suited for cichlid environments. Onyx is most effective when used alone as an integral substrate bed, but it may be mixed with other gravels or sands. Onyx is not chemically coated or treated but does have a slight buffering capacity. 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 Onyx bed is not disturbed. Slight initial cloudiness is normal and will clear rapidly (212 hours). To shorten the cloudiness period use Clarity in conjuction with mechanical filtration (such as filter floss). To determine the number of bags required for your aquarium, please note that each bag (7 kg, 15.4 lbs) occupies a volume of approximately 7,000 cm3 (425 cu. in.).