How to Install Undergravel Filter Aquarium: Step-by-Step Guide for Beginners

Are you looking for an efficient and affordable way to keep your aquarium clean and healthy? Installing an undergravel filter could be the solution you’ve been searching for. This type of filter system is easy to install and low-maintenance, making it perfect for beginners and experienced hobbyists alike. The undergravel filter works by pulling water through the gravel at the bottom of your aquarium, which helps to remove debris, unwanted chemicals, and waste.

It then sends the filtered water back up through the aquarium, creating a constant cycle of clean water. Installing an undergravel filter is a simple process that can be completed in just a few steps. First, you’ll need to gather all the necessary materials and equipment.

You can find an undergravel filter kit at your local pet store or online. Once you have your kit, you will need to prepare your aquarium by cleaning the gravel and removing any decorations or plants. Next, it’s time to assemble the filter.

This involves placing the undergravel filter plates in the bottom of the aquarium and securing them with lift tubes. You will also need to add a powerhead to the top of the lift tubes, which will create the water flow needed for the filter to work. After everything is in place, you can add your gravel back into the aquarium and decorate as desired.

Overall, installing an undergravel filter is a simple and effective way to maintain a healthy and clean aquarium. With just a few simple steps, you can enjoy crystal-clear water and happy, healthy fish.

What is an Undergravel Filter?

An undergravel filter is a type of aquarium filter that uses a perforated plate to draw water down through the gravel substrate, pulling debris and waste with it. This filter type is popular among aquarists because it’s affordable, easy to install, and requires minimal maintenance. To install an undergravel filter, start by thoroughly cleaning the tank, including the gravel substrate.

Next, place the filter plate over the bottom of the tank and secure it in place with suction cups or other fasteners. Then, add a layer of gravel on top of the filter plate to cover it completely. Finally, add water and any desired decorations or plants to the tank, and the filter will be ready to use! With proper care and maintenance, an undergravel filter can keep your aquarium clean and healthy for your aquatic pets.

Definition and Basic Features

An undergravel filter is a type of aquarium filter that is designed to sit beneath the substrate of your aquarium. These filters work by pulling water through a layer of gravel or sand at the bottom of the tank, which then traps debris and waste particles. The clean water is then released back into the tank through a set of uplift tubes, providing your fish with clean and healthy water.

Undergravel filters are a popular choice among aquarium enthusiasts because they are inexpensive, easy to set up, and low maintenance. They are also very effective at removing small particles and debris from the water, which helps to improve the overall clarity of your tank. When choosing an undergravel filter, it’s important to consider the size of your aquarium and the type of fish you have, as this will help determine the appropriate filter size and flow rate needed to keep your tank clean and healthy.

how to install undergravel filter aquarium

Pros and Cons of Undergravel Filters

An undergravel filter is a type of aquarium filter that is installed beneath the substrate of the tank. The principle behind this type of filter is that water is drawn down through the substrate and into the filter plate, where it is then passed through a layer of filter media before being returned to the tank. There are several pros and cons to using undergravel filters that should be considered before deciding if it is the right option for your aquarium.

One of the advantages of undergravel filters is that they are relatively inexpensive and easy to install. They also provide good biological filtration because they encourage the growth of beneficial bacteria in the substrate. However, undergravel filters can be difficult to maintain and can cause problems if not properly cared for.

They can also be less effective at removing larger particles and debris from the water compared to other types of filters. Additionally, they can be prone to clogging, which can lead to poor water quality and potential harm to fish and other aquatic life. In conclusion, the decision to use an undergravel filter in your aquarium requires thoughtful consideration of the pros and cons.

While they offer some benefits in terms of cost and biological filtration, they can also be difficult to maintain and potentially harmful if not properly cared for. As with any aquarium equipment, it is important to do proper research and consult with a professional before making a final decision.

Step-by-Step Guide to Install Undergravel Filter in Your Aquarium

Installing an undergravel filter in your aquarium may seem daunting, but it can actually be quite simple. The first step is to ensure that your tank is clean and free of debris. Next, carefully place the undergravel filter into the base of your aquarium, making sure that the air lift tubes are positioned correctly.

Once in place, it’s time to add the gravel and any decorations you desire on top of the filter. After adding water to your tank, plug in the air pump to activate the filter and let it run for a few minutes to ensure that everything is working properly. Regular cleaning and maintenance will help ensure that your undergravel filter continues to function effectively.

With a little bit of know-how, installing an undergravel filter can be a simple and effective way to keep your aquarium clean and healthy.

Step 1: Gather Materials and Tools

When it comes to setting up an effective filtration system for your aquarium, an undergravel filter is a popular and reliable choice. To get started with this project, you’ll need to gather a few essential materials and tools. First and foremost, you’ll need an undergravel filter kit, which typically includes filter plates, tubing, and a powerhead.

You’ll also need a suitable substrate, such as gravel or sand, to be placed over the filter plates. Additionally, you’ll need a heater, thermometer, and water testing kit to ensure your aquarium environment is properly regulated. Finally, you’ll need some basic tools like a net, bucket, and scraper to assist with maintenance tasks.

Once you have all of these materials and tools on hand, you can move on to the next steps of installing your undergravel filter system.

Step 2: Prepare the Aquarium

Once you’ve gathered all the necessary materials, it’s time to start preparing the aquarium for the undergravel filter installation. First, clean the aquarium thoroughly, making sure to scrape off any algae and remove any debris. It’s important to rinse the substrate (gravel or sand) multiple times until the water runs clear, as any dust or debris can clog the filter.

Once the substrate is clean, add it to the bottom of the aquarium, making sure to create a slope towards the back of the tank. This slope will help with water flow later on. Next, add any decorations or plants you wish to include in the aquarium.

Just be sure to leave enough space for the filter plates to be installed later. Finally, fill the aquarium with water, being careful not to disturb the substrate too much. Once the water is added, it’s time to move on to the next step in the undergravel filter installation process.

Step 3: Clean the Undergravel Filter Plates

When it comes to setting up an aquarium, one of the most important steps is to install an undergravel filter. And one crucial part of this process is cleaning the undergravel filter plates before adding them to your tank. The plates are responsible for filtering out any debris or waste that may accumulate in the substrate.

To clean them, start by removing the plates from the packaging and rinse them thoroughly with water. Next, use a brush or sponge to get rid of any grime or dirt that has collected on the surface. Be sure to get into all the nooks and crannies of each plate.

Once you’ve finished cleaning them, place the undergravel filter plates at the bottom of your aquarium before adding your substrate. With this step-by-step guide, you’ll be on your way to a healthy and thriving aquarium in no time!

Step 4: Install the Undergravel Filter Plates

Undergravel Filter Plates Now it’s time to install the undergravel filter plates! These plates will sit at the bottom of your aquarium and act as the primary filtration system. You’ll want to make sure that you choose the right size for your tank – typically one plate per 12×12 inch section. Begin by thoroughly rinsing the plates to remove any debris or chemicals that may harm your fish.

Once rinsed, place the plates in the bottom of your tank, ensuring that they fit snugly against the bottom glass. Make sure to leave enough space around the edges for water to flow through. Once the plates are installed, add your gravel on top of them to create a stable base.

Be sure to add enough gravel to cover the plates completely, as this will help with proper water flow. And there you have it – your undergravel filter is now installed and ready to go!

Step 5: Place the Filter Media

Now that the undergravel filter plate is set up, it’s time to place the filter media on top of it. This is what will trap all the harmful substances in your aquarium and keep it clean. Choose a high-quality filter media like activated carbon or bio-balls to ensure maximum efficiency.

Rinse the filter media thoroughly before placing it on the plate to remove any dust or debris. Make sure to distribute it evenly around the tank, covering the entire plate. It’s also important to clean it regularly to prevent clogs and ensure optimal performance.

With the filter media in place, your aquarium is now ready to provide a clean and healthy habitat for your fish.

Step 6: Add the Gravel

Adding gravel is an important step when installing an undergravel filter in your aquarium. Not only does it provide a natural-looking substrate for your aquatic pets, but it also helps to promote the growth of beneficial bacteria that will help keep your tank clean. Make sure that the gravel you use is washed thoroughly to remove any dirt or debris.

This will help to prevent cloudy water and other issues down the line. Once you’ve washed the gravel, spread it evenly across the bottom of your aquarium. The layer of gravel should be at least two inches deep to ensure sufficient filtration.

Don’t worry about stirring up the substrate too much – the water flow from the undergravel filter will take care of any settling gravel. With the gravel in place, you can move on to the next step in setting up your undergravel filter.

Step 7: Connect the Air Pump

Now that you have laid down the filter plate, it is time to connect the air pump. This is a crucial step in the installation of the undergravel filter, as it creates the necessary flow of water through the filter media. Attach the air pump hose to the air stone and place it on top of the uplift tubes.

Make sure that the air stone is securely in place and the hoses are tightly connected to prevent air leaks. Turn on the air pump and observe if there are any bubbles rising from the uplift tubes. If you see bubbles, then your air pump is successfully working, and you have successfully installed your undergravel filter.

Just remember to clean your filter regularly to maintain a healthy and clean environment for your aquatic pets.

Maintenance Tips for Undergravel Filters

Installing an undergravel filter in your aquarium is a great way to maintain a healthy aquatic environment for fish and plants. To start, make sure the filter system is properly sized for your tank. A good rule of thumb is to use a filter that covers at least 1 inch of the tank’s bottom surface area.

Once you have the right size filter, you can begin installation. First, add a layer of gravel to the bottom of the tank, followed by a plastic grid. The grid should be placed over the gravel and fitted snugly against the tank walls.

Finally, add a second layer of gravel to cover the grid. This creates a space for water to flow through the gravel and filter debris. To maintain the filter, regularly vacuum the top layer of gravel to remove any debris that has collected.

It’s also important to periodically clean the plastic grid and check the water flow rate to ensure proper filtration. With these tips, your undergravel filter can keep your aquarium clean and healthy for your aquatic pets.

Regular Cleaning and Gravel Vacuuming

If you’ve decided to use an undergravel filter in your aquarium, it’s important to know that regular cleaning and gravel vacuuming are essential for maintaining good water quality. Undergravel filters work by pulling water through the substrate, which can trap debris and waste. This means that you’ll need to perform more frequent and thorough gravel cleaning to prevent accumulating dirt and waste buildup.

Using a gravel vacuum to suck up debris while doing a water change helps ensure that the substrate stays clean, reducing the chances of harmful bacteria and algae growth. By keeping up with your maintenance routine, your undergravel filter will continue to function properly, providing effective biological filtration for your aquatic pets. Overall, the key to successful undergravel filter maintenance is simply staying on top of regular cleaning and gravel vacuuming.

Monitoring Water Flow and Air Pump Performance

If you have an undergravel filter in your aquarium, it’s essential to monitor the water flow and air pump performance regularly. These components work together to create a healthy environment for your fish and other aquatic creatures. One essential maintenance tip for undergravel filters is to clean them regularly.

Over time, debris and waste can clog the filter, restrict water flow, and reduce performance. You can easily clean the filter by turning off the air pump, lifting the filter plate, and vacuuming the debris from the gravel. Also, check the air pump regularly to make sure it’s operating correctly.

A malfunctioning air pump can cause poor water flow and decreased oxygen levels, which can harm your aquatic pets. You can monitor the air pump by listening for unusual noises, checking the airflow rate, and inspecting the air-stone for clogs. Overall, proper maintenance of your undergravel filter can help create a safe and healthy environment for your aquarium inhabitants.

Replacing Filter Media and Plates

Undergravel filters are a popular choice for many aquarium hobbyists, offering an affordable and effective way to keep the water in their tanks clean and healthy. However, like any other equipment, these filters require regular maintenance to function properly and deliver optimal results. One essential aspect of maintaining undergravel filters is replacing the filter media and plates periodically.

Over time, the filter media becomes clogged with debris and waste, reducing its effectiveness in removing impurities from the water. Therefore, it needs to be cleaned or replaced every three to six months, depending on the tank’s size and inhabitants. The filter plates also need to be checked and replaced if they are cracked or damaged, as they play a crucial role in providing oxygen to the bacteria that break down waste in the substrate.

By following these simple maintenance tips, aquarium enthusiasts can ensure that their undergravel filters perform at their best, keeping their aquatic pets healthy and happy.


In conclusion, installing an undergravel filter in your aquarium can seem daunting at first, but with a little patience and some basic understanding, it’s a piece of cake. Just remember to properly clean the gravel and place the filter plates evenly, and soon your aquatic friends will be breathing easy in their crystal clear environment. So don’t be afraid to get your hands wet and embrace the underwater world – and if all else fails, just tell your fish to figure it out themselves.

After all, they’re the experts in living in water!”


What is an undergravel filter and how does it work in an aquarium?
An undergravel filter is a type of filter that is placed below the gravel substrate in the aquarium. It works by drawing water down through the substrate, which helps to remove debris and waste from the water.

What are the benefits of using an undergravel filter in an aquarium?
Undergravel filters can promote a healthy aquarium by providing excellent biological filtration and oxygenation. They can also help to reduce the amount of maintenance required to keep the aquarium clean.

What types of fish are best suited to using an undergravel filter?
Most types of freshwater fish can thrive in an aquarium with an undergravel filter. However, fish that are particularly sensitive to water quality, such as discus or angelfish, may require additional filtration.

How do I install an undergravel filter in my aquarium?
To install an undergravel filter, you will need to follow the manufacturer’s instructions carefully. Generally, this involves placing the filter plate or plates under the gravel substrate, and connecting an air pump to the lift tubes.

Can I use an undergravel filter in a saltwater aquarium?
Yes, undergravel filters can be used in saltwater aquariums. However, they may need to be supplemented with additional filtration methods, such as a protein skimmer or a canister filter.

How often should I clean my undergravel filter?
The frequency of undergravel filter cleaning will depend on the size of the aquarium and the number of fish. Generally, it is recommended that the filter be cleaned every 2-4 weeks.

Are there any downsides to using an undergravel filter in my aquarium?
Undergravel filters can be effective, cost-efficient, and easy to maintain. However, they can also be unsightly and may require more frequent gravel cleaning to prevent debris buildup.