Picture by: Cacoa Pleco
Protein skimmers are one of the most important components of a salt-water aquarium. Protein skimming is also called "foam fractionating". These are the most useful in removing dissolved organic compounds from your tank. The greatest advantage of protein skimming is that it removes the organic compounds before they break down and poison the water. Phenols and yellowing agents in a tank can effectively be removed using a protein skimmer. Organic matters that get dissolved in water are a major source of food and nutrition for undesirable elements like micro algae and slime algae. Protein skimmers also curtail lime nitrate and phosphate build-ups.
Basically, a protein skimmer removes the larger molecules from water. Originally, the term protein skimmer came into existence because people believed that protein skimmers help in removing protein from water. But, afterwards it was found that protein skimmers also help to remove all sorts of dirt from the water.
What actually happens when you run the protein skimmer is that it creates a huge column of bubbling water within the tank. Dirt, sludge and organic compounds stick to these bubbles. But, these bubbles are usually too small to be seen by the naked eye. Once the dirt sticks to them, the bubbles begin to float up. When the bubbles reach the surface, they burst and deposit their collection of waste matter into the collection cup. The collection cup prevents the dirty deposit from slipping back into the column of water. The nature of salt water aids protein skimming, and because of this very reason, protein skimming is not feasible in freshwater.’
Based on scientific experiments, it was proved that driving a large collection of bubbles through a huge column of water leaves the water purer and cleaner. The success of any protein skimmer also depends on the size of the bubble it produces. Limewood is used in most protein skimmers to bring out the "perfect bubble". The co-current protein skimmer uses an open-ended tube or cylinder. The source that produces the bubbles is mounted at the base. The water is drawn up into the cylinder from the bottom, bubbles are passed through this, and once the bubbles burst leaving their debris in the collection cup, the purified water will be released into the tank. But, because of the time needed, this is not the most efficient method of protein skimming.
The Mazzei valve does not use limestone or an airstone to produce bubbles. A venturi valve delivers the many millions of bubbles that are to be used for purification. This is a very efficient system and is the professional aquarists first choice of protein skimmers. But, recently a newer and simpler form of protein skimmer became very popular. The "ETS" or Environmental Tower Skimmer or the Down-Draft Skimmer use a long tube that is connected to a sump. Bioballs are placed inside the long tube. This diffuses the high velocity of water. As the water passes over the Bioballs, they get smashed time and again. By the time the water reaches the base of the sump, it is foamy and thick. Huge volumes of water can be purified in this manner.
In most saltwater aquariums, protein skimmers are equivalent to life-support equipments. Increased levels of organic matter in a tank are the first indication of poor maintenance. Few forms of life will thrive in such waters. The goal of protein skimming is to get all these organic compounds out of the water. Since it physically separates the dirt from the water, protein skimmers come under the category of mechanical filtration. Another huge advantage of the protein skimmer is that it is an ONGOING filtration system that helps to keep your water clean on a continual basis.