Spa recirculation water filter installation having an upwardly, inwardly open recess in the plastic spa water reservoir molded in a similar recess in a female mold. Water outlet fittings in opposite walls of the recess connected in a T-manner to a recirculation water pump. A filter having in each end a fitting interengaging with the water outlet fittings to secure the filter in place. A compression spring in one filter end fitting to be compressed during engagement and disengagement of the filter end fittings with the water outlet fittings. A cover over the filter installation with flanges secured to the filter end fittings.