How a protein skimmer works

A protein skimmer is the heart of any aquarium equipment, so understanding how it works is crucial.

The principle of a protein skimmer can be simply summarized as foaming. Because foaming is a great way to create foam, some people also refer to protein skimmers as "bubble machines."

In detail, the skimmer generates a large number of small bubbles. These bubbles have charged electrons on their surface, which can carry away proteins from the water as they expand. Because the surface tension of the foam is relatively high, the skimmer effectively utilizes this surface tension to separate and squeeze out proteins. The viscosity of the foam changes as the surface area grows and expands, and as the bubbles gradually disappear.

Simply put, the working principle of a protein skimmer is that the tension of bubbles pushes dirt out of the water, separating it from the water. Once the dirt is separated from the water, the O₂ concentration in the water is reduced, and consequently, the NO₃ concentration is also reduced. The protein separated by the skimmer is stored in a liquid-like form in a collection tank and then periodically cleaned out.

Based on the working principle described above, protein skimmers currently come in various types: air pump, needle pump, brush pump, and external, built-in, and plug-in.

Saltwater aquariums have higher requirements than freshwater aquariums. The proteins in seawater also primarily come from biological metabolism, but these are harmful and are generally soluble or semi-soluble in water. However, seawater, combined with its protein skimmer and salinity, can quickly remove NO₂ and NH₃-producing substances from the water, reducing the burden on the nitrifying system. Protein skimmers effectively reduce the pressure on nitrifying bacteria, and this is the working principle of the skimmer.