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 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. The pump has to be at least 35 cm underneath the water.
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. An 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.
5. Starting/Performance
The system can be started when the skimmer is correctly installed. After switching the pump on, air is
automatically drawn into the skimmer. To minimize the noise level, connect the air inlet tube with the blue
connecting piece of the sound absorber supplied. Fix the sound absorber with the holding plate on the aquarium
or filter system above the water level. The needle wheel breaks the air into small bubbles. This method
eliminates the greater proportion of the noise. After the initial start, some hours may pass before the first foam
is pushed into the collection cup. This is due to a reaction between the surface of the acrylic glass and aquarium
water. Equilibrium of electrical charges takes place. After a maximum of 24 hours, the foam should be pushed
evenly into the collection cup. The quantity of liquid and organic substances is dependent on the pollution of the
aquarium.
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