A multiple cartridge fluid filter canister for mounting operatively in a standard filter housing includes spaced part upper and lower support plates that engage respective ends of a plurality of elongate filter cartridges that extend between the upper and lower support plates. The upper support plate carries an upper positioning element that depends from the upper support plate for engaging an upper end of a respective filter cartridge. The lower support plate carries a corresponding lower positioning element that extends upwardly from the lower support plate to engage a lower end of the filter cartridge. Annular seals surround the upper and lower positioning elements for respectively interengaging and sealing the upper and lower ends of the filter cartridge to restrict fluid flow between the cartridge and the upper and lower support plates. The upper and lower support plates define one or more inlets and outlets that communicate with corresponding fluid flow inlet and outlet lines in the filter housing.