Aqua Medic multi reactor Gen II is designed to operate either directly inside the aquarium or inside the filter sump. With the supplied holding unit, the multi reactor can be mounted horizontally on the aquarium glass. The pump needs to be fully submerged to prevent air suction. The entire body may only be submerged maximum up to the outlets on top of the unit. The immersion depth of the unit can be adjusted by opening the clamp screw. If the reactor cannot be put deeply enough into the water due to a low water level, splashing noises can occur. By turning the new water level control, the water in the reactor can be accumulated which minimizes splashing noises.Aqua Medic multi reactor - Gen II M+ for use in the aquarium or filter sump+ space-saving due to internal water supply+ highly efficient filtration due to high flow through your chosen filter media+ adjustable water flow+ very simple maintenance due to removable filling tube, the filter housing incl. Pump can remain in the aquar