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Protein Skimmer Filtration System

How Does A Protein Skimmer Work?

A protein skimmer is a fantastic alternative supplemental filtration device that is essential for effective freshwater and saltwater aquariums. In addition to that, they are successful at removing protein and other organic matter, this in return helps maintain a healthy habitat.

Moreover a protein skimmer can assist your primary filter in having better performance, as well as other water quality and clarity benefits.

Types Of Protein Skimmer Filtration Systems

There are many types of protein skimmer filtration systems to choose from, but they will fit on into one of these four categories:

  • Hang-On-Back (HOB): These are protein skimmers that hang on the walls of your aquarium. They are suitable for tanks that do not have a sump. They also have an additional appearance of a power filter that hang on the walls of your tank and they’re more suitable for smaller aquariums(under 100 gallons).
  • External: These will tend to run externally off an aquarium sump. This means that the sump water will feed into skimmer, then the clean water will return the ‘clean’ water into the sump.
  • In-Sump: These are produced so that they fit inside the sump of your tank. These are by far the most popular choice by aquatic hobbyists, which means a greater range of cost and sizes.
  • In-Tank: These can also be refereed to as ‘Nano’ skimmers as they’re the smallest skimmers you can get as they will not take up too much room in an aquarium. Despite their size, ‘Nano’ skimmers do a very good job at remove organic waste compounds

How Does A Protein Skimmer Remove Waste

Protein Skimmers rely their active waste removal process on adsorption. This is when organic waste adhere to the surface air bubbles that then get removed from the water through a removable waste cup. More specifically the mixture of aquarium water and air in the reaction chamber of a protein skimmer generates hundreds of these skimmer bubbles.

Benefits Of Using Protein Skimmer

These bubbles then progress along the skimmer and waste attaching itself to the bubbles will then migrate to the skimmer collection cup, which can then be removed. This process of active waste removal then enables mechanical, chemical and biological filtration to process more effectively.

How Effective Are Protein Skimmer Filtration Systems?

Protein Skimmers are very effective filtration systems, as they can help other filter systems that use mechanical, chemical and biological filtration systems ensuring clear and pristine water quality for your inhabitants.

Down below we will list different aspects of filtration systems and how protein skimmers can aid them in maintaining your aquarium.

What Is Mechanical Filtration?

Mechanical filters assist with improving the aquarium water quality. They do this by physically trapping and removing visible particles from the water by the use of filter media layers.

Whilst you might not visibly see the organic waste material, it will still be contaminating the water filter column. This means that if your mechanical filter media is not serviced and cleaned, then the waste and other organic pollutants such as Ammonia or Nitrite, will release itself into the fish tank which can be harmful to inhabitants.

What Having A Protein Skimmer Can Improve Mechanical Filtration

Alternatively, protein skimmer filtration systems extract the organic waste out of the water. Then they produce a foamy waster material called ‘skimmate’, which then ends up in a collection waste cup. This cup is removable which means you can then empty it from the aquarium, so it doesn’t leak back into the tank environment.

What is Chemical Filtration?

Chemical filtration alternatively relies on adsorption for removing organic waste. This means that if you do not service and clean this filter media layer, it will also lessen its effectiveness.

In some cases that have been mention among aquatic hobbyists, harmful bacteria and chemicals can leak back into the fish tank if your do not replace your chemical media layer.

What Having A Protein Skimmer Can Improve Chemical Filtration

Funnily enough adsorption occurs with a protein skimmer too, in the surface of each bubble. This means as long as you service your protein skimmer, there will be a constant supply of waste-binding area. This provides you with effective and efficient waste collection and removal, without replacing any media levels or the worry of its leaching into aquarium again.

What is Biological Filtration?

On the other hand, biological filtration breaks down nitrogen elements through aerobic beneficial bacteria method. This means that the Ammonia and Nitrite in your tanks get converted into the less harmful compound of Nitrate.

Although, even Nitrate can be harmful for Corals and other reef invertebrates. Without proper biological filtration systems, many aquariums have a build of harmful Nitrate levels in their environment which can be harmful towards their inhabitants.

What Having A Protein Skimmer Can Improve Biological Filtration

More effectively, a protein skimmer will reduce Nitrate by slowing down build-up. This is because it is able to remove organic waste before it even has an opportunity to break down and release their nitrogen compounds into the water. Using a protein skimmer in a reef aquarium is essential as coral and species that live in coral can be very sensitive to Nitrate.

Benefits Of Using Protein Skimmer Filtration Systems

Whilst we’ve outlined the types of skimmers and how they can benefit your aquarium, we’ve also have other additional benefits of using them that you may interested in:

  • They assist in maintaining a healthy pH. level by putting a stop to Carbon Dioxide build-up and acidic conditions.
  • When used in combination with a sump, they will support a developing large bioload.
  • Improve viewing of aquarium, as it removes oily surface of water which can also improve light for inhabitants.
  • Reduce the levels of Phosphate, which reduces the growth of Algae.
  • Removes the toxins that are released from corals and Algae.


Ultimately using a protein skimmer can deal with aquariums that can be difficult to maintain and clean. The best choice of protein skimmer can be relative to your tank and what type of skimmer you use, more on the best protein skimmers for you aquarium can be found here.

In-Sump Protein Skimmer

In end, by opting to use a protein skimmer, you’ll be able to ensure that you have the most effective cleaning solution for your aquarium environment and its inhabitants.

About The Author

the aqua guru author

Jon is an aquarium keeper of over 15 years and the owner of Guppy's, Betta's and other marine life. He always likes to make changes to his aquarium for the benefit of his marine life's well-being and health using the best aquatic products on the market. You can read more about us here.