What is a Protein Skimmer?

Protein Skimmers, also known as Foam Fractionators, are mechanical devices used to remove organic waste materials from seawater. Protein skimmers are highly beneficial to maintaining water quality in marine aquariums. Using a protein skimmer will provide clearer water, more efficient biological filtration and an improved dissolved oxygen level.

How Does a Protein Skimmer Work?

Protein Skimmers work by mixing large volumes of small air particles into a column of water. Organic wastes, primarily proteins, are attracted to the air/water interface of the injected bubbles, and collect on the bubbles surface. The attached organic materials then rise up the column of water with the bubbles, and collect on the surface as foam. The waste foam, known as Skimmate, is pushed up the neck of the protein skimmer, and trapped in a collection cup or waste line to be discarded. Protein Skimmers work efficiently in salt water, unfortunately they do not work well in freshwater aquariums. Freshwater lacks the ability to form the fine air bubbles that makes these devices efficient in salt water.

Different Types of Protein Skimmers

Protein skimmers come in many forms, with the two most common being the Hang On Back (HOB) and the In Sump versions. There all also external models, which are less commonly used by hobbyists. The primary difference between all skimmers is the method of producing air bubbles, Skimmers have seen the development of many forms of air injection over the years. Early Protein Skimmers used compressed air and airstones for air delivery, this was an efficient method, and is still used some smaller models of air driven skimmers today. High pressure venturi driven injection became popular as an effective method of air injection, and is also still used in some models. Most Protein Skimmers now use a combination of a venturi to draw in air, with a specialized pump impeller to chop or fractionate the air. These type of skimmers using Pin Wheel, Needle Wheel or Mesh Wheel impellers are highly efficient, and capable of mixing huge volumes of air and water, with much less energy consumption of the earlier models.

Skimmer body design has also seen many changes, most notably with the newer cone shape skimmers, and space saving designs, that allow powerful skimmers to take up a minimum of valuable real estate in filter system. There are skimmer choices available for just about any application.