Phosban Reactor Extension Kit UPC: 748172548523 Manufacture: Two Little Fishies The PhosBan Reactor maximizes efficient use of chemical filter media. Up-flow principle pushes water from the bottom upward through the dispersion plate to gently fluidize chemical filter media. Even distribution of aquarium water through the PhosBan Reactor increases media contact for optimized use of PhosBan or other chemical filter media. Includes barbed hose connections for 1/2" ID tubing and ball valve to fine tune flow rate. Appropriate size pump*, tubing, and media required (not included). Multiple reactors may be used for larger aquariums.