If you have a saltwater aquarium, the protein skimmer or foam-fractionating filter, is the most important item you need to keep your tank clean and healthy. The protein skimmer is most effective at removing dissolved organic compounds before they start to break down and require your biological filter to remove.
The process of skimming only works with saltwater due to the nature of the water itself. The salt in the water creates friction when it rubs against the air bubbles, creating a charge. Because opposites attract, the air bubble is attracted to the oppositely charged wastes and combine into one unit until they float to the top of the water column. The bubbles then burst, releasing the wastes into a skimmer cup for collection.
The introduction of a skimmer will significantly reduce the amount of orgainc waste in the saltwater or reef aquarium and increase the water quality which will greatly decrease the amount of nuisance algae growth.
Counter-Current Protein Skimmers
The Beckett style of protein skimmers utilize a foam injector nozzle that must be powered by a powerful pump to generate the pressure necessary to create the tiny air bubbles in the foam. Beckett protein skimmers are among the most efficient skimmer designs. The Beckett Corporation was the first to manufacturer this specific type of foam injector nozzle, but many foriegn companies have copied the design to produce similar products.
Spray induction protein skimmers integrate a spary nozzle directly below the surface of the water inside the column. At the bottom of the water column the air bubbles are then broken into smaller bubbles before rising to the top to export the waste.
Downdraft skimmers use a venturi to spray water at high velocity into a column that contains bio-balls. The bio-ball media disrupt the water flow, creating air bubbles. The bubbles are then diverted into a sump box, where they interact with the water to be treated, and then rise to the top to the collection cup.
Aspirating Needle Wheel
The aspirating needle whell design also goes by various other names including: pin wheel, Adrian wheel, and mesh wheel. The needle wheel consists of an impeller that integrates pins positioned perpendicular to the base. The pins serve to disperse the air introduced via a venturi valve into smaller, finer air bubbles.
Co-Current Protein Skimmers
These popular models do not use an air stone to introduce the air; they use a venturi valve. The venturi style skimmers are similar to the counter-current models except instead of an air stone, they use the venturi to introduce large amounts of air bubbles. They require a much shorter column and are far more efficient. The only drawback to this style is they require a powerful pump to drive the air through the venturi valve.
The size and quantity of the bubbles created in the water column affect the efficiency of the skimmer. The co-current skimmers have the source of the bubbles (typically an air stone), mounted on the base of the column and use the volume of bubbles created to lift the wastes to the top of the column to be skimmed off into the collection cup.
Since the air bubbles travel fast up the column, a longer column is required to be effective. To be more efficient, the bubbles have to dwell in the column as long as possible, so they collect the wastes before bursting at the surface.
Protein Skimmer Manufacturers
- Red Sea
- Aqua Medic