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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 1000 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 water out of the aquarium or filter chamber, mixes it with air in the pump
housing which is then cut into small air bubbles by the Aqua Medic 3D needle wheel. This water/air
mixture is then pumped into the reaction pipe where organic substances are taken up by air
bubbles. Foam is formed and pushed into the foam cup. The purified water leaves the skimmer via
outlet and is directed back to the aquarium or filter sump by the discharge (Fig. 1, No. 8).
4. Set-up
The EVO 1000 is a skimmer that can be directly mounted on the aquarium edge “Hang on”, (Fig.
4).
Fig. 4: EVO 1000 in “Hang on” operation
Set-up:
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 fitting (Fig. 1, No. 10).
The length of the flexible hose should
be as short as possible.
A fixing of the pump at the glass pane is not necessary. The pump must
be placed directly below the surface because the air intake will decrease and the water flow will
increase if it is mounted deeper. This would lead to humid foam and fine air bubbles.
A 8-mm air tube is connected to the air injector (Fig. 2, No. 10) 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 (Fig. 1, No. 13). This will be connected to the holding plate and fixed at the outside
above
the water level.
