An internal reticulated foam filter for a water filtration tank is an apparatus that thoroughly filters water of a variety of water filtration tanks. The apparatus includes a flow-management assembly, at least one inner tube, at least one outer tube, and a plurality of foam filters. The flow-management assembly positions the apparatus around a distributing tube of a water filtration tank. The at least one inner tube upholds the plurality of foam filters against a central tube of the distributing tube. The at least one outer tube releases the water filtered by the plurality of foam filters back into the water filtration tank. The flow-management assembly also includes a first cap, a second cap, a plurality of main inlets, a plurality of channels, and a plurality of main outlets. The plurality of main inlets is in fluid communication with the plurality of main outlets through the plurality of channels.