Abstract: The invention provides an integrated water treatment system suitable for use in the treatment of contaminated water, wastewater, potable water, aquaculture, industrial water and polluted water bodies. An integrated water treatment system according to at least one embodiment of the invention comprises a plurality of modules adapted to float in a body of water integrating a plurality of different attached growth biofilm media types positioned within a plurality of water flow paths and circulations. The conditions provided by a multiple of media types and plurality of flow paths creates a multiplier effect increasing the number of treatment zones and an increased diversity of interconnected treatment process zone types.