Seachem Onyx Sand Size:7kg Purigen is the highest capacity

Purigen is the highest capacity organic filtration resin on the market

12 month warranty (conditions apply)

For freshwater and marine environments

without any chemical treatment

Seachem Onyx Sand Size:7kg Purigen is the highest capacityDescription 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