Using An Undergravel And A Power Filter Together: A Good Idea?

There are many different items that you are going to have to purchase for your aquarium. You need filters, rocks, gravel, plants/other decorations, and a few other odds and ends. The filter is one of the biggest priorities and we are going to discuss 2 types of filters;  undergravel filters and power filters.

 Undergravel filters are placed under the gravel and power filters are hung on the back of the tank and more widely used. There are 2 types of power filters; regular and internal. There seems to be no clear or concise answer as to whether or not you can use these 2 filters together. It is going to be your best judgment that decides.

While we have done extensive research to answer the question; can a power filter and undergravel filter be used together? We are going to provide you with the best possible answer that we can. We are also going to include in depth information on both types of filters. But when choosing your filter, remember there are more than these 2 types, so you may need to do a little extra homework.

Again, it is going to be your final call as to whether you use the undergravel and power filter together. There is no black and white, yes or no answer. 

What Is An Undergravel Filter

An undergravel filter is exactly what its name suggests. It is a filter, usually plastic, that you lay on the bottom of your fish tank. With the undergravel filter you need to use gravel to cover it up, at least 2 inches. Sand will fall through the grate and then your filter will not work properly. Your undergravel filter will come with the plastic grate, lift tubes, and power heads or an air pump. 

How Does An Undergravel Filter Work

As stated above, the plastic filter plate will lie under the gravel of the tank. The plate will allow the water to freely flow under the gravel. The gravel is going to act as the mechanical and biological filter as the water is drawn through it. To move the water in your tank you will either need an air pump or a power head.

The air pump is going to produce bubbles at the bottom of the lift tubes. Then the bubbles push the water up the lift tubes and into your tank. The powerhead is going to pump the aquarium water out of the top of the lift tubes and into the tank.

Whether you choose the air pump or the power head; the water that is moved out of the lift tubes is replaced with water from under the filter plate. The gravel, acting as the mechanical filter, actually catches the large free floating particles/debris. 

How To Install And Undergravel Filter

Installing an undergravel filter, just like any other filter, is fairly simple. Besides installation, we will give you the top 3 undergravel filters in this section. 

Make sure you have a filter that is perfect for your tank size and water volume. You are going to have to install this type of filter before you puter water or anything else in your tank. This is the time to make sure your tank is clean. Wiping it down good ensures that is not dust/debris stuck to the glass on the inside of the tank. Dechlorinated water is the best option to clean your aquarium, tubing, and any decorations. 

The box that your undergravel filter came in should include clear and precise directions; so here are the basics.

  • Connect the hard plastic tube to the baseplate. Do not use too much force or you could bend the pieces
  • Connect one end of the airline to the bubbler. Make sure it is extremely secure over the valve of the bubbler
  • You will then place the bubbler inside the housing tube. This connects the bubbler to the output vent
  • Take the free end of your airline and connect it to your pump. To avoid splitting the plastic tubing, push the tube on slowly.
  • Place your baseplate/filter on the bottom of your tank. Try to get it as centered as you can, with the tubing at the back of the tank. This will ensure that the bubbles do not ruin the view of the fish
  • Now you can pour your gravel in. You will need approximately 2 pounds of gravel for every gallon of water. You want at least 2 inches of gravel on top of the plate/filter. 

Now you are ready to add your décor, water, and your fish. It is recommended that you change ¼ of the water each week to keep the filter running smoothly. You also need to make sure you siphon or vacuum the gravel each time you change the water. This gets the extra food and waste off of the gravel and helps keep the water clean.

Top 3 Undergravel Filters

01). Imagitarium Undergravel filter: 28.5 x 11 inches. It is under $10 for a 29-gallon capacity filter. It works with freshwater or saltwater tanks, you get 2 filter cartridges, and it is a two-plate system. Check Imagitarium Undergravel Filter on Amazon here

02). Lee’s Original Undergravel Filter: it weighs 1 pound for the 5.5 gallons and is 7.5 x 15 inches. This filter is made of high-quality plastic and has an optional flow-thru set-up to use with a powerhead. Check Lee’s Original Undergravel Filter on Amazon here.

03). Aquarium Equip Undergravel Filter: This 10-gallon capacity filter is 5.9 x 11.8 inches and weighs 0.45 pounds. The filter plate can be used with an air pump, submersible powerhead, filter pump, or hang-on filter (power filter). It also comes with an adjustable lift tube and also works with freshwater or saltwater tanks. Check the Aquarium Equip Undergravel Filter on Amazon here.

We have covered a lot of information on the undergravel filters. We are now going to explore the power filter world and afterwards we can decide if the 2 types of filters are compatible and can/should be used together. 

How It Works and The Maintenance

The basics of the power filter; it draws water up the lift tube and it goes into a filter chamber where the water is then pushed through a series of filter media, which will provide biological, chemical, and /or mechanical filtration.

Once it goes through the media it will flow back into your tank. You can either have an air-pump, that will produce air bubbles that will lift the water into the lift tubes; or you may have a water pump that will pull water through the lift tubes. 

To maintain (or clean) your power filter, you need to first unplug the filter. Take the power filter off of the tank and put it in the sink or a clean bucket. You then want to remove whichever media you have chosen to use. If it is disposable, toss it, if it is refillable you want to discard the media inside so it can be refilled.

You are going to want to clean the whole unit, very well with dechlorinated water. Do NOT use any kind of soap. The residue left over from the soap can harm the fish and the chemistry of the tank. Replace or refill your choice of media, hand the power filter back on the tank and partially fill with some of the tank water.

You are going to want to clean your filter every 3 to 4 weeks, depending on tank size and how many fish you have in your tank. In conjunction with your filter clean/change it is also recommended that you do a ¼ water change as well. Siphon or vacuum the substrate to clean up any leftover food, debris, and fish waste. 

Top 3 Power Filters

You want a power filter that covers the nitrogen cycle: basically, this when your fish eats, then excretes, and the stages the excretions go through (which produces ammonia and other toxins). This is the main reason for a filter in an aquarium; to remove the waste, bad bacteria, ammonia, and other junk. 

01). Aqueon Quiet Flow 20: this features 4 stage filtration; mechanical, chemical, biological, and wet/dry. This provides you with the healthiest, cleanest, and clearest water. It has an internal pump that lessens the noise, eliminates leaks, and restarts automatically after power outage or cleaning. This best feature on this filter is the LED warning light that flashes if the filter is clogged or when it is time to replace it. Check Aqueon Quiet Flow 20 on Amazon here.

02). Fluval C Power Filter: It is under $25 for a filter that can handle a 30-gallon tank/water capacity. You can use this in freshwater or saltwater and it has a 5-stage filtration system; foam, polyester, carbon, bio-screen, and c-nodes. In simpler terms, it captures debris, filters out the particles, absorbs odors and impurities, biological filtration aces, and allows for beneficial bacteria growth. It is also easy to clean, has a patented filtration system, and a versatile design. Check Fluval C Power Filter on Amazon here.

03). AquaClear Power Filter, made by Hagen. This includes multi-stage filtration, fits almost all aquariums, and has 5 available models. The unique design of the filter allows for six-time more media volume. Aqua clear has a patented re-filtration system, CycleGuard multi-stage filtration system, and a warranty. Depending on which AquaClear Power Filter you choose, you will need to replace the media every 1-3 months. The filter will preserve the beneficial bacteria that give your fish and live plants stress-free living and helps to maintain clear water in your tank. Check AquaClear Power Filter on Amazon here.

Power Filter vs. Undergravel Filter

Now that we have discussed both, let’s compare them. In their own right, they both do the job that they are designed to do. By the end of this segment we will be able to tell you if you can/should use them together. As stated in the beginning, it is basically going to be a trial and error decision because there is no clear yes or no answer.

Some of the main differences between the two filters are as follows:

  • One hangs on the back of the tank, the other sits on the bottom under the gravel
  • Power filters can handle large amounts of water per house and more effectively
  • Power filters will require more maintenance than undergravel filters
  • Undergravel filters do not use the 3 major types of filtration as the power filters do
  • Undergravel filters are less expensive and work with any style of tank
  • Power filters do not work well with tanks that have hoods

Undergravel Filter Pros and Cons

1. No or minimal moving parts
2. Your gravel is your filter media
3. Virtually invisible
4. Easy installation/set-up
5. Builds up beneficial bacteria fairly fast
6. Versatile; use with various powerheads, special media types, and other accessories
1. You have to have a vacuum and you will need to clean the gravel regularly for the undergravel filter to be effective
2. They do not work well with fish or other creatures who like to burrow or dig in the substrate. The fish could get sucked underneath the filter.
3. Possibility of creating noxious gasses and dead spots if not cleaned regularly or properly
4. The installation has to occur before you can add the water, decorations, or fish.
5. If you do not put enough gravel in the water, the smaller fish can get sucked under the baseplate
6. They produce a lot of underwater circulation, which is an issue for rooted plants.

Power Filter Pros and Cons

1. Easily handle large quantities of water. The right size for your set-up and they will be very efficient
2. Most power filters hand on the back, outside of the tank. So it will not take up space inside the tank
3. Power filters normally have the 3 stages of filtration (some have more)
4. Easy to install and use
5. Fairly easy to maintain and clean
6. Budget-friendly
1. You have to take it apart from every now and then and clean the inside
2. Can not be submerged, it can break the power filter
3. Required to clean/change the media every 1-3 months
4. They require an open-top tank. This could allow for evaporation of the water, and possibly fish jumping out of the tank

Both filters work great, in their own way. It is all going to depend on your set-up, what you prefer, and your budget.


In all of my research, as I have stated before, there was not a clear answer on whether or not the 2 filters could be used in conjunction with each other. I believe you could use an undergravel filter and a power filter together, especially in the bigger tanks (say 50+ gallons). You would get the benefits of both of the filters at the same time. Also, if one went down you would have the backup already installed and running. So, if you were gone for a weekend, you wouldn’t come home to a filthy tank and possible dead fish. 

So, with all the information we have provided to you, you can make your own decision as to whether or not you feel that both filters can be used together. If you attempt it and it doesn’t work, you are not really out anything, as both filters are fairly inexpensive. Plus, you will have a back up filter in case of an emergency or something happens and one goes down. In my opinion it would be a trial and error situation. 


I'm passionate about fish pets and love sharing everything I learn about them.

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