When Should I Connect Undergravel Filter With Canister Filter?

For aquarium tanks, the filters play a critical role. They ensure a suitable water environment for your aquatic inhabitants. One of their most important benefits is reducing nitrate, which can kill your fish.

Aquarium filters are available in many types, including wet/dry filters, Canister filters, internal power filters, Undergravel filters, and more.

The cool thing is that you can combine them in some cases. So when should you use the Undergravel filter with Canister filters? Let’s read to find out!

When Connect the Undergravel Filter With the Canister Filter?

The Undergravel filter

You can pair the Undergravel filter With the Canister filter when you need to clean the Undergravel filter plate.

To maintain the Undergravel filter, you must clean the substrate with frequent gravel vacuuming, as this filter will pull debris into the gravel bed.

If you do not regularly wash the substrate, the debris will be pulled beneath the filter plate, and it might be a haven for muck to settle.

One of the most effective ways of cleaning your Undergravel filter plate is to mount a canister filter’s inflow tube to the uplift tube.

After that, put this outflow tube into one bucket and enable your canister filter.

All the accumulated debris will be sucked out from under the filter plate into your waste bucket.

Finally, it will effectively clean your filter and change the water simultaneously.

How Do Undergravel Filters Work?

The Undergravel filter has many benefits for aquariums

The Undergravel filter mainly provides biological filtration from the good bacteria in the substrate, turning debris into plant food as one part of your tank’s Nitrogen cycle:

Step 1: The air pump will generate suction, pulling dirty water through the screen and substrate to the bottom of the aquarium.

Step 2: The water will go up the lift tube, through the media cartridge, where it can mix with air and bubble back into the tank.

Step 3: Big debris is trapped in the substrate and will ultimately be consumed by bacteria.

Step 4: Finer particles will be collected under the screen, and a matrix of biofilm will be formed.

Step 5: Some can go up the lift tube and get trapped in the cartridge.

Main Issues With Undergravel Filters

The Undergravel filter is cheap and comes in various sizes that fit standard-sized tanks from 10 to 55 gallons.

It works well for a small planted tank as debris decaying under and in the substrate delivers nutrients live plants can utilize. It also acts similarly to air stones and oxygenates the aquarium water.

However, it has limitations, including:

  • Undergravel filters are very limited as they cannot hold much media.
  • This filter may not be very effective initially.
  • You cannot bury the screens too deeply.
  • This filter is not adjustable once it is in place.


How to Put the Undergravel Filter in Place?

You will need to find one empty aquarium, one appropriate air pump, and plastic aquarium tubing.

  • Step 1: Put the lift tubes and screen in the bottom of your empty tank.
  • Step 2: Cover this screen with a few inches of the gravel layer.
  • Step 3: Utilize plastic tubing to connect your air pump to the filter.
  • Step 4: Pour dechlorinated water into your tank.
  • Step 5: Plug your air pump in. Then, your filter will bubble.

What Is A Canister Filter?

The canister filter

The canister filter provides superior chemical, mechanical, and biological filtration for any larger aquarium or fish tank with many fish.

Its body, also known as the “canister” portion, is dramatically larger than the power filter in most cases.

Depending on the model, the canister filter will have one large media basket or more to carry different filter media kinds.

Each media type will be layered on top of each other to keep excellent water quality. Compared to the power filter, the canister one requires more effort to maintain or set up. But it will raise your eyebrows with its filtering power.

This filter will work great with South American and African Cichlid aquariums, planted aquariums, as well as saltwater aquariums.

What Are the Benefits of a Canister Filter?

Canister filters are considered to be more efficient than other types of filters and are disposable.

There are some reasons for it, including that you can choose the kind of media that is proper for your aquarium. The filters are good for reducing nitrate levels.

Another feature of this filter is that the clean water that has been filtered will be sprayed back into your aquarium in a way that lowers both current and splashes and can also lower evaporation.

If your tank is particularly close to the wall, canister filters can be helpful due to the way it is situated.

Should I Use an Undergravel Filtration System: Pros and Cons?

Here are five pros and five cons of using Undergravel filters:


  • Undergravel filters are Invisible.
  • Undergravel filters are effective.
  • No moving parts, simple to install & operate.
  • Undergravel filters are inexpensive to acquire and operate.
  • Undergravel filters are versatile and can be used with other filters.


  • Undergravel filters can’t be used with diggers
  • Undergravel filters can produce noxious gasses
  • Can make fish get trapped under the plates
  • Undergravel filters may present a problem with plants
  • Undergravel filters are hard to maintain, especially for long-term

What Are Types of Aquariums Best Suited for Undergravel Filters?

Here are three types of aquariums that will work well with Undergravel filters:

  • Small Tanks
  • Breeding Tanks
  • Hospital/Quarantine Tanks

How Many Filter Types Are Used for Aquariums?

Filter Type Cost Range Setup Skill Level Effectiveness: Mechanical Effectiveness: Chemical Effectiveness: Biological
Wet/Dry Filter High Advanced Medium Medium High
Canister Filter Medium-High Intermediate High High Medium
Internal Power Filter Low-Medium Basic Medium Medium Medium
Power Filter   Low-Medium Basic Medium Medium Medium
Undergravel Filter Low-Medium Basic Low Low Medium
Air-driven Internal Filter Low Basic Low Low Medium

The Bottom Line

You can connect your Undergravel filter with a canister filter when you need to clean your substrate. Thanks to that, you will remove all of the debris from under the filter plate. Thanks for taking the time to follow us!