How To Choose The Right Protein Skimmer For Your Tank

This entry is part 6 of 8 in the series Filter types

Choosing a protein skimmer for your aquarium can seem like a straightforward task, but this cannot be farther from the truth. Without knowing what features to evaluate, you may end up purchasing a protein skimmer that is highly incompatible with your tank.


This article aims at showing you how to select the right protein skimmer for your aquarium.

Having adequate knowledge of the types of protein skimmer will help you determine which is perfect for your aquarium.

Types of protein skimmers

Various types of protein skimmers exist, and they all adopt a different method of cleaning an aquarium. Continue reading to learn which skimmer is most suitable for your aquarium.

HOB protein skimmer

HOB protein skimmer

HOB or hang on back protein skimmers are mostly installed on aquariums that don’t have a sump or enough room to house an in-tank protein skimmer. HOB skimmers mostly come in the shape of a flat box, which allows it to be hidden when placed at the back of an aquarium.

In order to keep your aquarium clean, HOB skimmer applies a co-current technique of water interfacing. The HOB skimmer uses a pump to extract water from your tank and then mixes it with air before the waste is removed into the collection cup.

The essential components of a HOB skimmer are known as the pump and impeller. It is these components that create the bubbles in the water. Waste and protein then attach themselves to these bubbles before they are collected.

This skimmer is easy to install if you follow the instruction manual accordingly. However, it should be noted that these skimmers are mostly used on aquariums holding up to 100 gallons of water.

In-sump protein skimmer

In-sump protein skimmer

In-sump protein skimmers are designed to rest in the sump system of an aquarium.

A sump is a smaller tank discreetly positioned below the aquarium, away from sight. In simpler words, a sump is an external reservoir that can store filtration devices.

In-sump skimmers are essential for the prosperity of medium to large reef aquariums. That is tanks which contain corals and a plethora of fishes.  These are the most popular types of skimmers, and they are available in a wide range of sizes.

In-sump skimmers are versatile filtration devices. They offer different methods of skimming. Different models of this skimmer exist ranging from downdraft driven to spray bar, and others come with combined skimming abilities.

This skimmer is recommended for aquarium owners who do not want pieces of equipment crowding their aquarium when they could be concealed and kept out of sight.

When selecting your in-sump skimmer, it is necessary to consider the size of your sump. In-sump skimmers are easy to configure and are generally required to be submerged under a precise level of water.

In-tank protein skimmer

In-tank protein skimmer

This type of protein skimmer is installed on the inside of your aquarium. Most of them come in small sizes to ensure they don’t take up too much space in your aquarium. However, don’t be deceived by their size. They are high performing skimmers that will leave your tank spotless.

In-tank protein skimmers were one of the earliest skimmers to be applied in a saltwater aquarium. These straightforward devices simply use an air pump driven airstone to create bubbles, collect the waste on the bubbles and release it into a collection cup.

In-tank skimmers are easy to install, and you don’t have to worry about your aquarium water leaking onto your floor since they are placed in the tank.

There are different varieties of in-tank skimmers, but one, in particular, stands out more than the rest. These one are known as nano protein skimmers, and they are ideal for nano-reef tanks.

Reef aquarium owners prefer nano skimmers because they are excellent in maintaining the water quality of a tank.

External protein skimmer

External protein skimmer

External protein skimmers are designed to be installed outside of the aquarium and connected to the aquarium sump. It extracts polluted water from the sump and replaces it with clean water.

External skimmers are usually installed in large aquariums or aquariums with no space in their sump. These external protein skimmers come in a large size and have several pumps to filter large amounts of water.

External Skimmers are an excellent option for cleaning your tank, but you must remember to clean your collection cup regularly. When it gets overloaded, the odor it produces can be overpowering and unpleasant.

What type of protein skimmer is right for your tank

Selecting a protein skimmer for your aquarium is a big decision to make. This decision can become harder to make if you are unaware of the features the skimmer should possess. Consider the following factors before you purchase a protein skimmer.

Aquarium size

The size of your aquarium determines the kind of protein skimmer you need.

So before you spend your money on a skimmer, ask yourself, how much aquarium space do you have for a skimmer?

Some aquariums come with a sump that can store your skimmer. If you don’t have one, you can choose to get an in-tank skimmer or an HOB skimmer. 

The capacity of a protein skimmer is stated by the manufacturer. This capacity will tell the aquarium owner if the skimmer is capable of handling the size of this aquarium.

Also, the number of fishes in your tank coupled with the amount of food loaded into your aquarium can also determine the type of skimmer you need.

The efficiency of the protein skimmer

Before committing to a protein skimmer, evaluate the capabilities of such skimmer to determine if it can handle your aquarium.

For instance, the pump of a skimmer is the component that supplies the skimmer with aquarium water. This gives you an idea of just how essential the pump is, and without a strong pump, you are guaranteed to get a low-performing skimmer.

Secondly, protein skimmers use air bubbles to extract waste from your tank’s water. This is why you need to know how much air bubbles such a skimmer can produce. Different models of skimmers apply various methods to generate air bubbles.


Do not pay attention to only the amount of air bubbles being produced, but also consider the size of the bubbles.

Medium-sized bubbles will clean your aquarium faster than the tiny or large ones. 

Lastly, you can go through the reviews of people that have purchased the protein skimmer in question to verify if their protein skimmer operated well or if they were satisfied with their product. 

Hide it or display it

Most aquarium owners prefer their filtration device out of sight. So they don’t favor in-tank skimmer but would rather go for in-sump or HOB skimmers.

Even when they purchase these skimmers, they tend to go for the ones that can easily be concealed and hidden away.

Are you the kind of aquarium owner that would prefer a skimmer that can be easily hidden? Or do you not mind displaying your protein skimmer?

Whichever category you fall into, you can factor that in when searching for a skimmer for your tank.


Hopefully, this buying guide helped you narrow down your options when choosing a protein skimmer for your aquarium.

However, if you don’t just rely on only one factor but consider all of them, we are confident you would find the perfect skimmer in no time. We said in no time because we have compiled a list of the best protein skimmer, and you might just find the right one here. 

Do not hesitate to ask us any questions you might have regarding this topic.

Series Navigation<< What is a Protein Skimmer? Do You Really Need It for A Successful Aquarium?Protein Skimmer Overflow: What Causes It And How To Fix It >>