Seachem Onyx Sand is a naturally dark gray sand that perfectly complements and enhances the appearance of any aquarium. It provides not only iron and other minerals but supports optimal KH levels for freshwater planted aquariums. Being carbonate rich, Onyx Sand provides an advantage to any plants able to utilize bicarbonates. Although ideally suited to planted aquaria, it may be used in any aquarium environment. Onyx Sand 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. Onyx Sand is not chemically coated or treated but does have a slight buffering capacity that may raise pH by 0.1 – 0.5 pH units (depending on source water characteristics). Onyx Sand is good for the life of the aquarium and need not be replaced.
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 4,250 cm3 (260 cu. in.). To determine your desired volume multiply tank width by length by desired depth. This bag is sufficient for about a 3.5 cm (1.5 inch) deep bed in a typical 40 L (10 US gallon) tank.
Although it is pre-washed, because Onyx Sand is a natural product, it may become dusty in transit and require rinsing before use to remove any residual dust.
3.5 kg, 7 kg
Units=mg/kg, source: Plasma Emission Spectrometer, EPA Method 6010, Univ. of Georgia Chemical Analysis Lab
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