Phalanx™ granular media package filter systems are custom-designed in circular or rectangular tankage with unit capacity from 20 gpm to over 1500 gpm (multiple units used for higher flow rates). A brand member of Poseidon Filtration Systems™, Phalanx is used for conventional water treatment, wastewater tertiary filtration, biologically active filtration, GAC adsorption and ion exchange, as well as denitrification (DDBF™).