Hepper is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Marineland Magnum Polishing Internal Canister Filter Review 2023 – Pros, Cons & Verdict

Lindsey Stanton Profile Picture

By Lindsey Stanton

If you are on the hunt for a new filtration system for a fairly large aquarium, you’re likely to come across the Marineland Magnum Filter. It is a fairly compact filtration unit, an internal one, that is designed for large tanks and utilizes all major types of filtration. Today we are doing a detailed Marineland Magnum Polishing Internal Canister Filter review to see if it’s suitable for your aquarium. We take a detailed look into its features, pros, and cons to help you decide if it’s the right option.

wave tropical divider

Our Marineland Magnum Internal Canister Filter Review

Marineland Magnum Polishing Internal Filter


The Marineland Magnum Internal Filter is an impressive filter for several reasons. Yes, like most filters it does have some drawbacks. However, generally speaking, this does seem to be one of the better internal filters. Let’s take a closer look at it to see what it is all about.

Filtration Capacity

Ok, so first and foremost, the filter is designed to be used with aquariums up to 97 gallons in size. At the same time, it has a processing power of up to 290 gallons of water per hour. In other words, it is a pretty good option for larger tanks. Now, if you have a 90-gallon tank, this filter can process the entire water volume of that tank over 3 times per hour.

This is a fairly strong and efficient filter, but if you have a really heavily stocked tank, we would not recommend using it for anything over 7 gallons. This way, the filter can process the entire water volume of the tank over 4 times per hour. This way you can ensure that the Marineland Magnum keeps the water in your tank very clean and clear.

Filtration Types

One good feature of the Marineland Magnum Filter is that it comes with all 3 major types of filtration. In other words, this is a 3 stage filter that engages in mechanical filtration for the removal of solid debris, biological filtration for the removal of ammonia, nitrates, and nitrites, as well as chemical filtration for the removal of other toxins, colors, and odors.

To be clear, all filtration media comes included here, including a Rite-Size floss sleeve, Bio Spira, and Black Diamond Carbon. Now, these types of media are not the best, but they do get the job done. They work well enough to remove most impurities and debris from aquarium water. For a simple 70-gallon tank that is not too heavily stocked, this media will do fine.

Clown fish in aquarium tank
Image Credit: Jordan Tan, Shutterstock

2 Media Chambers

What is pretty neat about this filter is that it comes with dual filtration chambers. The point here is to allow you to customize the type and amounts of media that you can use. If you like, you can add more of one type of media and less of another. It’s really up to you. This high level of versatility makes the Marineland Magnum a pretty attractive choice for many people, especially those who like to have a lot of biological filtration capacity.

Size & Placement

Yes, this is an internal filtration unit, which means that it takes up a bit of space in the tank. It comes in at around 8 inches in diameter and just over a foot (12 inches) in height. So, it will take up a fair amount of space in any fish tank. Though it should not be used for anything under 50 or 60 gallons, the space it takes up is relatively small compared to the overall tank size. With that being said, it does still take up more space than any kind of external filtration unit.

In terms of placement, the Marineland Magnum comes with suction cups to make things easy. It does not have to sit at the bottom of your tank. Simply plaster it onto the interior wall of your tank wherever you see fit using the suction cups. Surprisingly enough, the suction cup included is quite stable and secure. Just be sure to place it vertically, as it cannot be placed horizontally.

Self – Priming & Maintenance

What is pretty cool about this internal submersible filter is that it is self-priming. Because the motor is already submerged, you do not need to perform any manual priming, which is often quite annoying. Also, seeing as this is a canister filter, it comes with quite a decent lid with secure clips. All you have to do is take the lid off to clean the interior. It really does not get any easier than that.

Water Polishing

Something else that should be mentioned here, since it is in the name of the product, is the optional water polishing. This unit comes with a reusable pleated micron cartridge that can be charged with diatomaceous earth to further increase its filtration efficiency. The cartridge, since the filter has room for lots of media, can be kept inside of the filter if you so choose, or you can take it out and replace it with other types of media too, hence why this water polishing feature is labeled as optional.

To be clear, this feature is intended to remove any remaining fine debris from the water that the mechanical media is not able to remove. It is a beneficial feature, but for some people with lightly stocked tanks, it might actually be a bit of overkill.

large fish tank with plants and filter
Image credit: M-Production, Shutterstock


Overall, the Marineland Penguin is durable. It is made with pretty solid internal components that should last for quite some time assuming the filter is looked after. The outer shell is made of really rugged plastic to ensure that the filtration unit does not break down within the tank. This also helps because it ensures that no electrical components get exposed to the water, which is bad for the filter itself and for your fish too. While it is not the number one most durable aquarium canister filter on the market, it’s no weakling either.

  • Quite durable.
  • Lots of processing power.
  • Good for larger aquariums.
  • Lots of media capacity, customizable.
  • Polishes the water.
  • Easy to clean and maintain.
  • Self-priming.
  • Engages in all 3 major types of filtration.
  • Not very small or compact.
  • Makes a fair bit of noise.
  • Included media could be a little better.

clownfish divider2 ah


In case you are not a huge fan of the option we just reviewed, the Marineland Magnum, you can always take a look at the Marineland Magniflow canister filter. It is intended for 55-gallon tanks and smaller, so it is a bit smaller than the Magnum.

Also, the Magniflow looks a little different and has dual pumps, plus it is actually an external filtration unit, so it does not take up any space on the interior of the tank.

Yes, this is why the Magniflow is better, but in terms of the filtration media included, overall power, media capacity, and processing capacity, it is not as good or powerful as the Magnum.

Simply put, the Magnum is better for larger purposes, whereas the Magniflow is better for slightly smaller tanks.

aquarium plant divider


All in all, we think that the Marineland Magnum Polishing Internal Canister Filter is a pretty decent option to go with. Besides a couple of minor cons and drawbacks, it is one of the better internal canister filters for medium and large tanks out there right now. It’s fairly durable, easy to set up and maintain, and it does a great job in terms of aquarium water filtration.

You Might Also Be Interested In: Marineland Magniflow c360 Canister Filter Review

Related Articles

Further Reading

Vet Articles

Latest Vet Answers

The latest veterinarians' answers to questions from our database