Best Pond Filter for Your Backyard Fish Pond - Backyard Boss
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Best Pond Filter for Your Backyard Fish Pond

A backyard fish pond is one of those features that completely changes your landscape. If you don’t keep up with maintenance, it might change your landscape in a negative way.

Having the best pond filter system for your specific situation is a vital weapon in any pond keeper’s arsenal. As always, the options you have at your disposal are endless. So, to save you time and help you make the best decision, Backyard Boss has swooped in and reviewed the best filters on the market. Read through the post below and let us cut your work out for you.

Backyard Boss Top 5 Pond Filters for 2021

OASE BioSmart 5000 - Best Pond Filter for Your Backyard Fish Pond OASE BioSmart 5000
  • Volume: 5,000 gallons
  • Pump included: No
  • Warranty: 3 years
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Koral Filters Pro - Best Pond Filter for Your Backyard Fish Pond Koral Filters Pro
  • Volume: N/A
  • Pump included: No
  • Warranty: Risk-free satisfaction guarantee
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Pond Boss - Best Pond Filter for Your Backyard Fish Pond Pond Boss
  • Volume: 500 gallons
  • Pump included: Yes
  • Warranty: 1 year limited
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Total Pond Pressurized Pond Filter - Best Pond Filter for Your Backyard Fish Pond Total Pond Pressurized Pond Filter
  • Volume: 1,200 gallons
  • Pump included: No
  • Warranty: 1 year
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VIVOHOME Submersible Pond Filter - Best Pond Filter for Your Backyard Fish Pond VIVOHOME Submersible Pond Filter
  • Volume: 1,180 gallons
  • Pump included: Yes
  • Warranty: 3 months
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Why You Can Trust Us

I remember moving into a house that had a slimy, green puddle in the corner of the yard that used to be a fish pond. My dad built an elaborate-looking filter out of buckets and gravel and sand to get rid of algae in the pond. The pond came back to life. It turned into the best feature in the yard.

Since that time, I’ve built many DIY filters myself. Some worked. Plenty didn’t. But I learned something from each one I built. Today, I’m combining all the lessons I learned along with market research around what filters are available into the post below.

If you’re looking to get rid of algae in your pond, you’re in the right place. Learn from my mistakes, read this post, and make an informed decision about what you need to keep your backyard pond in tip-top shape.

Best Pond Canister Filter

OASE BioSmart 5000
    This advanced biological filter takes the hassle out of keeping your pond clean. Let the filter do the work so you don't have to.



Why We Like It: Keeping your pond clean isn’t something you can automate. There will always be somebody that has to clean out filters once in a while. This chore is often an unpleasant one, so OASE has simplified the process. Keeping your pond crystal clear has never been easier than with their BioSmart canister filter.

They’ve even included an indicator that lets you know when it’s time to clean the filter and tells you the water temperature. With OASE, guesswork is a thing of the past.

Who Should Buy It: If your pond is 5,000 gallons or smaller and you’re struggling to keep it clean, the OASE BioSmart might just be what you need.

There are plenty of reports about how this product was the secret weapon that turned a problem pond around. Also, if you loathe cleaning the filters in your pond, the ease with which you can clean this filter will be right up your alley.

Best for Koi Ponds

Koral Filters Pro
    This roll of filter material provides superior mechanical filtration wherever you need it. Cut it to whatever shape and size you need.



Why We Like It: This filter pad comes in a huge roll that you can cut to size and re-use. That means you can add an element of mechanical filtration wherever you feel necessary.

Wrap it around your pump basket to keep your pump free of debris and running smoothly. Wrap another piece around your hose outlet for an extra line of defense. This filter pad does a great job of filtering out any particles suspended in your pond water.

When it’s full of gunk and restricting the flow of water, you can simply remove the pad, hose off all the grime, and put it back in place. Easy.

Who Should Buy It: This filter pad is designed exclusively for koi ponds and saltwater ponds. If you’re looking for an extra level of filtration for your koi pond that will fit any shape or needs you may have, this pad might help.

Best for Small Ponds

Pond Boss
    This combined pump and filter kit is a money saver and an Earth saver. Quiet operation and eco-friendly materials.



Why We Like It: Everything you need for pond filtration, as long as your pond is 500 gallons or smaller. This kit comes with a pump, a filter, and a nozzle with various options for water displays. Buying the full kit ends up being cheaper than buying each component separately, and there will be no second-guessing whether or not the filter is compatible with the pump.

Pond Boss has taken extra care to ensure the pump uses as little power as possible. The addition of BioBalls to the filter system helps grow beneficial bacteria, which means your pond stays cleaner for longer.

Who Should Buy It: If you have a pond of 500 gallons or smaller, this pump and filter kit is for you. Because everything you need comes in one box, you can plug it in and start cleaning your pond as soon as you’re ready. If electricity cost is an issue, you can be sure that this pump uses as little power as possible.

Best UV Pond Filter

Total Pond Pressurized Pond Filter
    This pressurized filter keeps water moving so debris doesn't get a chance to settle. The three step system makes algae blooms a thing of the past.



Why We Like It: This filter is on a mission to make algal blooms a thing of the past. The sealed and pressurized filter keeps the water moving so that debris doesn’t have a chance to settle. The water then goes through a mechanical filter, a biological filter, AND a UV filter to make sure that algae stands no chance.

Who Should Buy It: If you’re losing the battle against algae in your pond, you may have just found your secret weapon. This filter can be installed in-line with your current system. So you can fit this filter inside or outside your pond. Wherever suits you and your needs best.

Best Filter and Pump Kit for Larger Ponds

VIVOHOME Submersible Pond Filter
    This submersible filter comes with a pump and fountain kit included. Choose from three different water patterns to add some motion to your pond



Why We Like It: This one has it all. Three different types of filters, a pump, and a fountainhead. All packaged together in a relatively compact design. Simply plug and play for a clean pond.

Who Should Buy It: If you’re looking for one kit to do it all, this is the one for you. Especially if you have a pond of 1,180 gallons or less, simply hook this kit up and enjoy clean water and three different spray patterns.

How Does a Pond Filter Work?

Most pond filters have a few different elements that work together to create the clean pond of your dreams. The first step of most filters is to block larger debris from entering the inner workings of the filter.

This is important to prevent blockages in parts of the system that are difficult to access. Because this is where larger organic matter gets trapped, it’s important to keep an eye on this and clean it out regularly to avoid your pump running dry.

The next step of most pond filters is where the beneficial bacteria live. These are tiny microorganisms that feed on things that contribute to algal blooms and generally unhealthy water. They are a vital part of keeping the ecosystem of your pond in balance.

Without beneficial bacteria, your pond might end up with dangerous levels of ammonia and nitrites, which lead to all sorts of knock-on problems for the life in your pond.

Another type of filter uses UV light to kill off all bacteria and microorganisms. This can be effective in combating algae in your pond, which will leave you with clear water.

Some filters use all three of the above methods to leave you with crystal clear water. Let’s take a closer look at the most common types of filters used today.

Goldfish In A Fish Pond
Image credits: Katherine McAdoo via Unsplash

Types of Pond Filters

Mechanical Filters

The mechanical filter is your first line of defense. This is often the most basic element of your filtration system. Even though some may argue that it’s the most important. This is where the pond skimmer vs. pond filter debate comes in.

The mechanical filter is there to collect large debris before it enters your filtration system. Things like leaves or other vegetation, trash that may be blown in, or your dog’s favorite ball.

It’s important to clean this filter often as large debris can easily block it. A blockage here means the rest of your filtration system runs dry. And this is a problem for the next stage of your filtration system; the biological filter.

Biological Filters

This is the stage in your filtration system where you are essentially creating a great environment for beneficial bacteria to thrive. Biological filters are often filled with lots of small objects. They are mostly made of plastic, and sometimes have a fancy name like Bio Balls.

No matter what they’re called, their purpose is the same: provide as much surface area as possible for the bacteria to colonize. A healthy colony will consume all the smaller bits of detritus suspended in the water that passes through the mechanical filter.

These bacteria are responsible for breaking down ammonia and nitrites in the water and are an essential element in keeping your pond water clean and healthy. A healthy colony of beneficial bacteria is considered by some as the most important part of your filtration system.

UV Filters

Sometimes known as UV clarifiers, their purpose is to combat green water. They do this by sterilizing the water by killing off all microorganisms and bacteria associated with algae.

As we learned in the section above, not all bacteria are bad. Some bacteria are vital to the health of your pond. The problem with UV filters is that they don’t know the difference. They kill off all but the hardiest species of bacteria.

Relying on a UV filter is fine if you are looking for a pond devoid of microorganisms and you’re able to quickly replace the filter when it fails. Once it fails, it won’t take long for your pond ecosystem to be wildly out of balance and the algae will quickly take over.

An alternative for fighting algae could be introducing algae-eating fish into your pond.

What to Look for in a Pond Filter

Fish Pond With White Statue
Image credits: Wonderlane via Unsplash

Your pond filter needs to match the size of the pump in your pond. The maximum flow rate of your filter needs to be the same as, or more than, the flow rate of your pump. This way you can be sure that your filter does what it needs to do without restricting the flow of water, which could lead to a burned-out pump.


The volume of your filter and, therefore, your pump, needs to match the volume of your pond. If your pond is 500 gallons, a pump and filter combo designed for a 200-gallon pump won’t be up to the job.

Alternatively, a pump and filter combo designed for a 1,000-gallon pond will be overkill. In some cases, this might lead to a burned-out pump. But most of the time it’s simply a more expensive option when a cheaper one would do.

Although this post isn’t about pumps, the following is worth mentioning. The most important thing your pump needs to do is cycle water, obviously. But you don’t want that water to be circulating under high pressure.

The best pond pumps are low-pressure, high-volume pumps. This means you can peacefully cycle the water through your pond and filters without creating a tsunami at the bottom.

Compatibility With Size and Number of Fish

The next thing you need to consider when choosing your filter and pump combination is the number and size of fish you have in your pond.

This is where the importance of an effective mechanical filter comes in. The mechanical filter should prevent any fish from entering the filter system of your pond. If your fish have access to the inner workings of your filter you’re in for some trouble including blocked filters and dead fish.

The filter is also responsible for cleaning up any excrement the fish produce. And this is where the size of your filter is important. The more fish you have and the bigger they are, the bigger your filter should be.

A filter can never actually be too big, and many installers recommend doubling the size of your filter. For example, a 1,000-gallon pond should have a 2,000-gallon filter.

This leaves no doubt that the filter will effectively keep the water clean enough for your fish to thrive.

Orange And White Koi In Pond
Image credits: Sora Sagano via Unsplash

How We Picked

For this guide, we focused on a range of filters so that you could find something no matter what your specific needs are. There are full kit options, with pump, filter, and fountainhead. All the way down to just the foam filter material that you can cut to whatever shape and size you need.

Fish Friendly: All of the options on this list are fish-friendly, so your fish will be safe and healthy with these filters in their environment. Not only do they keep your fish safe, but they filter all the toxins out of the water so that your fish are healthy enough to thrive, too.

Volume: These filters all have a flow rate sufficient for the oxygenation of the water as it moves through the system. This is important for the health of your fish as well as the countless microorganisms and beneficial bacteria that make up a healthy pond environment.

DIY friendly: Depending on your skillset and/or willingness to learn something new, all the items on this list could be installed by the average weekend DIYer. No special tools or advanced knowledge required.

The Final Verdict

The filter that claims our top spot is the OASE BioSmart 5000. This filter has been the savior for many a green, slimy backyard pond. You may have to make one or two easy adaptions to make it fit your system, but once it’s installed, the hard work is over. Being easy to clean is a top priority for the OASE BioSmart 5000.

There’s a useful indicator that will tell you when it’s time to clean out the filter, which is a breeze. There’s even a temperature read-out so you can be sure that your fish are comfortable and happy. All of this, combined with a reasonable price, makes the OASE BioSmart our top pick for fish pond filters.