The present invention is an aquarium filter that treats water mechanically, chemically and biologically, provides maximum and uniform circulation and aeration of water, prevents channeling, reduces surface debris, reduces leaking and clogging, maximizes the viewable area, facilitates a slim profile, while being uncomplicated to install and inexpensive. In an exemplary embodiment, the present invention is an aquarium filter comprising a first surface skimmer, a second surface skimmer, a first mechanical filter, a second mechanical filter, a plurality of drip trays, a plurality of biological filters, a first chemical filter, a second chemical filter, a pump and a conduit.