The Aqua Medic overflow box is mounted to the outside of the aquarium.

A constant water level is maintained after the start of the overflow. Water circulation is achieved by pumping the water up from the filter-sump into the aquarium, and then with the use of the overflow box back into the filter.
This makes it possible to connect aquariums to under the counter filters systems without having to drill holes in the tank. The overflow box is a completely constructed form acrylic.
For use with PVC 32mm

19 x 18 x 25 cm (LxBxH)
up to 2.500 l/h.