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3. Theory
Protein skimming is a method of physical water treatment. It uses a phenomenon known from our
daily experience: the adhesion of surface active substances to air water layers. If we add a drop of
oil to a water surface, a thin film is produced with a thickness of only one molecule. Surface active
compounds like proteins behave in the same way. The EVO 3000 uses its air bubbles to create a
large water surface for the waste substances to attach themselves to. These air bubbles are forced
into the reactor-pipe in a such a way that they undergo a long contact time within the counter-
current. Enriched with organic substances, they rise to the top and form a firm foam that is
dehydrated and pushed into the collection cup. This method removes organic wastes from the
aquarium water before they become part of the biological waste treatment cycle.
The venturi pump draws the water out of the aquarium or the filter chamber, mixes it in the pump
housing with air which is then cut into small air bubbles by the Aqua Medic 3D needle wheel. This
water/air mixture is pumped into the reaction pipe where the organic substances are taken up by air
bubbles. Foam is formed and pushed into the foam cup. The purified water leaves the skimmer via
the outlet (Fig. 1, No. 12) and is directed by gravity back to the aquarium or filter sump.
4.
Set-Up
The EVO 3000 is a “Hang on” skimmer.
Fig. 4: EVO 3000 in “Hang on” operation
Set up as an external skimmer on the aquarium (Fig. 4):
Assemble the necessary parts of the skimmer (see Fig. 1). Now, it can be attached to the aquarium.
Look for a protected place within easy reach - at the side or the back. The venturi pump is connected
with the pressure hose (17). The length of the flexible tubing should be as short as possible. The
pump must be placed directly below the surface because the air intake will decrease if it is mounted
deeper. A 8-mm air tube is connected to the air injector and fixed above the water level so the pump
can draw in air. Use the full length of the air hose which is attached to the sound absorber (22).
Now, the skimmer can be aligned with the aquarium. The two screws at the bottom of the skimmer
are adjusted in such a way that the skimmer is hanging safely on the aquarium. It is advantageous if
the skimmer is not 100% upright but leaning slightly (2º) to the aquarium (Fig. 4). The skimmer is
then not only hanging more safely, but also back-flow of water from the outflow box over the
aquarium frame is prevented. Both adjusting screws at the bottom are supplied with silicone suction
cups for increased safety. The skimmer is now ready for use and can be started.
