A protein skimmer is a unique piece of filtration equipment only found on saltwater aquariums.  A skimmer will remove waste and dissolved organic nutrients from the aquarium water while also helping to promote healthy gas exchange and stable pH.

Protein skimmers rely on a process called "foam fractionization" to remove the following contaminants from your aquarium water before it is broken down by bacteria and other microbes.

  • Uneaten fish foods
  • Fish waste
  • Suspended particulates
  • Undesirable coloring pigments - tannins

The waste concentrates in the protein skimmer collection cup which can then be removed on a regular basis. Skimmers are one of the most important nutrient exports methods you will engage in your saltwater tank.

How It Works:

The process of foam fractionization sounds more complicated than it really is.  The skimmer pump creates thousands of tiny air bubbles using aquarium water which creates a dense foam inside the protein skimmer body.  As the foam rises up the skimmer body, the tiny bubbles attract hydrophilic organic substances (waste). The bubbles gradually combine back together into larger bubbles as they rise, carrying that waste all the way up into the skimmer's collection cup where it can be removed.  

Learn More With A Diagram: What Is A Protein Skimmer?

Why Should I Use A Skimmer?

So we know a protein skimmer removes organic hydrophilic substances but how does that benefit your tank?  The answer is pretty easy to understand in that cleaner water creates a more stable and healthy environment for your fish and other tank inhabitants.

You will end up with less build-up of nitrate and phosphate which reduces the threat of unsightly nuisance algae outbreaks and promotes a healthy biome. Less nitrate and phosphate usually mean less frequent water changes and filter maintenance as well. 

The skimmer also removes those coloring pigments that give your aquarium water a yellow tint. The result is a better-looking tank without a yellow haze that obstructs viewing. This clarity also means you will achieve maximum light penetration through the entire water column without any obstruction from those coloring agents. 

A skimmer creates a dense foam, concentrated with tiny air bubbles which means a considerable amount of surface area where water touches air.  That means gas exchange is happening which ensures the tank water contains the right ratio of oxygen and CO2. This maintains a higher pH in the tank or better said, it reduces the amount of CO2 in the water which means less carbonic acid that drops the pH. If you pair your protein skimmer with a CO2 scrubber, you can further reduce that CO2 level which effectively eliminates that effect altogether. 

Specialty Applications

While a skimmer alone is an efficient nutrient export method, skimmers can also work alongside other filtration techniques such as Biopellets and Ozone. The biofilm produced by biopellets can be removed by a protein skimmer carrying nitrate out of the tank. When used with an ozone generator, the skimmer acts as a reaction chamber for ozone gas to effectively oxidize contaminants in the aquarium water. The skimmer along with activated carbon can then help to easily remove the highly-reactive ozone molecules before they are carried into your display aquarium.

Learn More With BRStv: Smarter than your Protein Skimmer? These Top Mistakes say otherwise!