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The Marineland Emperor 400 Pro Series Bio-Wheel Power Filter from Marineland is a powerhouse of biological filtration.

The filter includes two Bio-wheels that provide a living space for friendly bacteria, which filter out harmful chemicals in the water and help keep your fish happy and healthy.

The Emperor 400 also features a high flow rate, 3-stage filtration, quiet and efficient operation, adjustable intake, and a unique dual-pump design.

If you’re looking for an efficient and powerful filter with the best in biological filtration, the Emperor 400 just may be the best HOB filter for you.

Quick Overview Marineland Emperor 400 HOB

Marineland Penguin Power Filter, 50 to 70-Gallon, 350 GPH

Get The Marineland Emperor Power Filter
Value For The Money 99
How Quiet Is The Filter 95
Ease Of Installation 90
Ease Of Maintenance 95
Filtration Capacity 99
Flexibility, Flow Rate, Input, Output 90

The Best Features Of The Marineland Emperor

  • The Bio-Wheels are an extremely efficient way to up the biological filtration capabilities of your aquarium.
  • There is also a second intake in the middle of the intake tube to ensure all of your tank water is getting pumped into the filtration system.
  • This filter features a unique two-pump design.

Marineland Penguin Power Filter, 50 to 70-Gallon, 350 GPH

What We Liked About
The Emperor 400

  • Two Bio-wheels give you the best biological filtration possible.
  • 4 filter pad slots ensure all water passes through filtration media.
  • High flow rate and adjustable flow.
  • Extra-long, adjustable intake tube.
  • Durable, quiet, and efficient.

What We Don’t Like About
The Emperor 400

  • Need to be careful NOT to clean the Bio-wheels with tap water.
  • Spray bars can get clogged with debris, preventing Bio-wheels from spinning.
  • May become noisy after a lot of use (this can usually be fixed).

What You Need To Know About The Emperor 400

The Emperor 400 is an HOB aquarium filter that is powerful, efficient, quiet, and has unparalleled biological filtration with its two Bio-wheels.This filter also provides mechanical and chemical filtration through it’s 4 filter pad slots.

The Marineland is a very quiet and efficient filter and has a very high flow rate. It can handle 400 gph, and it’s rated for tanks up to 80 gallons.

This filter features a unique two-pump design.

The first pump pulls water through the intake tube and runs it through the filter, while the second pump pulls water into the spray bar system and sprays the top of the Bio-wheels, which makes them spin through the water.

[Video] How to Set Up and Install the Marineland Emperor 400 Power Filter

What About Those Bio-Wheels?

The Bio-wheels are the big selling point of the Emperor 400 and for a good reason. Bio-wheels are an extremely efficient way to up the biological filtration capabilities of your aquarium.

But there are some things you need to know about Bio-wheels before you jump into buying this filter.

Here’s how they work:

The Bio-wheels are made of porous material that provides a friendly habitat for beneficial bacteria to flourish.

Marineland Emperor 400 HOB Filter Spray Bar

Marineland Emperor 400 HOB Filter Bio Wheel

As the Bio-wheels spin, the bacteria come into contact with as much of your tank water as possible. This lets the bacteria break down harmful ammonia and nitrite in the water and convert them into the less-harmful nitrate.

This means healthier fish and a better-functioning aquarium.

When you clean your power filter, it’s crucial NOT to wash your Bio-wheels. Even just rinsing them with tap water will kill much of the bacteria living on them, and then you’ll be back to square one with your biological filtration.

We recommend just dropping them in the aquarium while you’re cleaning the rest of the filter.

Some owners of the Emperor 400 have reported that their Bio-wheels stop spinning after a while.

We have found that this is usually due to clogs in the spray bar system, so make sure you keep your spray bars free of debris and you shouldn’t have any problems.

Check out our HOB Filter Comparison Chart to compare popular Hang On Back Filters.

Hands On Marineland Emperor 400 HOB Filter

This filter is made of very high-quality materials and seems to be very durable. It’s made of a black plastic material that is both heavy and flexible, and seems less brittle than the clear plastic that you’ll find in other filters.

In our time with this filter, we’ve found that it’s tough to break, doesn’t leak, and doesn’t show wear as quickly as other HOB filters out there.

Many other filters out there have intake tubes that are too short, but the intake on this Marineland Pro Series Bio-Wheel Power Filter is very long. That means you can put your intake at the bottom of your tank.

There is also a second intake in the middle of the intake tube, which helps prevent dead zones and ensures that all of your tank water is getting pumped into the filtration system.

The four filter pad slots are a bonus, and you can easily swap out the included foam pads with bags of activated carbon or other filtration media if you prefer.

Buy The Marineland Emperor 400 Power Filter

Crystal clear water and healthy fish are a hallmark of this Marineland Power Filter. The high flow rate, efficient filtration, and dual Bio-wheels combine to make this one of the best filters on the market.

If you’re looking for efficiency, high water flow, and the best in biological filtration available, then you should be looking at the Marineland Emperor 400 Pro Series Bio-Wheel Power Filter .

Marineland Penguin Power Filter, 50 to 70-Gallon, 350 GPH
  • Certified flow rate of 350GPH, perfect for all aquariums up to 70-gallon, uses two Rite-Size C filter cartridges
  • Delivers easy, three stage mechanical, chemical, and biological aquarium filtration
  • Convenient Penguin Rite Size Cartridges come ready to use with each filter; Three-stage BIO-Wheel filters for freshwater and saltwater aquariums
  • Please refer the Product Manual, Set up Manual and the Instructional Video before use

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