10 High-Quality Pond Filters for Healthy and Clear Pond

Your pond is its own ecosystem – just like in nature!

However, unlike in nature, your pond will need some help from you.

Since your pond is a smaller body of water with little to no movement, you’ll need to keep the water clean. This is especially true if you want to provide a healthy and safe environment for plants of animals.

And, while regular care and maintenance are important, you’ll also want to invest in a quality filter.

Filters do a lot to help make sure your pond is a healthy, safe environment. From filtering out debris to keeping oxygen in the water, they’re one of your most important tools.

If you’re new to pond filters and this seems like a daunting task, no worries. We’ve compiled a complete buying guide to walk you through everything you need to know to pick the best pond filter.

The 10 Best Pond Filters

1. OASE BioSmart 10000 Pond Filter

The OASE pond filtration system, which can also be purchased in a smaller size for 5000-gallon ponds, is designed to be as user-friendly as possible.

It features both a cleaning indicator and water temperature display, helping you know the right time to clean your filter. As a result, even if it is your first pond filter, you’ll be able to operate it with ease.

It also offers an option for both biological and mechanical filtration.

Biological filtration uses natural growing bacteria to clean the water while mechanical filtration runs the water through different mediums. Having both options available will allow you to find out what works best for your pond.

An important thing to remember, however, is while this filter is designed to clean 10000 gallons, that’s with no fish. This means you may need to get a larger or secondary filter if you have a 10000-gallon pond with fish.

Related: Best Self-Cleaning Fish Tanks

2. Pondmaster PMK190

This small pond filter is designed to support ponds up to 200 gallons. As a result, it’s great for either smaller ponds or as a secondary filter.

However, if you are looking for a large pond filter, other purchasing options are available. Here, you’ll be able to find a variety of different sizes ranging from small pond filters to medium.

Also, thanks to the fountainhead, it provides a bell-shaped spray that will help improve the aesthetic of your pond. This fountain will also help keep the surface clear by providing a slight ripple.

This is also a beginner-friendly pond filtration system

First, it’s a kit with all the needed pieces, so you don’t have to worry about finding the right pieces. Second, it also provides mechanical and biological filtration to help keep your water clean and clear without chemicals.

3. POND BOSS Filter Kit

This filter kit includes everything you will need to maintain your background water feature, including a decorative fountainhead.

It is designed out of durable, non-toxic parts that make it eco-friendly. Not only that, but it also includes several innovative features to help save money and the environment.

The POND BOSS kit is designed to be energy-efficient with low water shutoffs and a UV pond filter.

This kit is beginner-friendly and includes everything you’ll need for installation and start-up – sans tools and pond of course. Once it is fully submerged, which you may need to weigh it down, it will run quietly.

Related: Check our guide about fish pond liners

4. CNZ All in One Pond Filter System with Sterilizer

The CNZ filter uses both mechanical filtration and sterilizers to keep your water clean and healthy for your plants and fish.

The mechanical filter uses a large coarse filter as well as three biofilters to help remove debris from the water. The UV light helps sterilize the water to kill any microbes, including bacteria and algae that can harm your water quality.

Since it is an internal filtration system, you don’t have to worry about disguising your filter like with external filters.

However, since this is installed in the pond, you will need to remove it to clean it. Thankfully, though, once you have removed the system from the water, it is easy to access the insides and clean.

This is also an entire kit with everything you need for an efficiently operating system. As a result, you won’t have to worry about trying to find the right pieces, making this great for beginner landscapers.

5. Goplus Pressure Bio Filter for Pond

The Goplus Pressure filter is a UV filter for smaller ponds.

If your pond has a normal fish load, this filter can support up to 2500 gallons, for a heavier fish load, 1500 gallons.

Since this is a UV filter, you can use it to kill any algae or harmful bacteria. Algae can decrease the amount of oxygen in the water, and bacteria can make your fish ill. 

This is an external filter that is easy to access and maintain, and it is suitable for garden or fish ponds.

6. Aquagarden 5 in 1 Water Pump and Filter

The Aquagarden filter offers more than just clean water that is safe for your fish and plant life. With it’s 5 in 1 design, you get a filtration system as well as:

• Four fountain heads
• A pump
• An automatic LED light
• And a UV filtration system as well as biological and mechanical systems

This is a small pond filter and only supports up to 200 gallons. The exact supportable size depends on the amount and type of fish living in your pond. 

Along with the UV filter to kill green algae and the ceramic biodome, the Aquagarden also provides three mechanical mediums. The coarse filter catches larger waste; the medium filer catches particles, and the polymer wool filter polishes the water and reduces cloudiness.

The three filtration systems erase the need for a secondary filter. The UV light kills algae; the biodome prevents algae growth, and the mechanical filter removes large debris.

To help maintain the aesthetic value of your pond, it also comes with four fountain heads to create a beautiful scene. And, so you can enjoy it no matter the time of day, it comes with an automatic LED spotlight to light up your pond.

7. Aquascape Submersible Pond Water Filter

If you have a pond filtration system but are looking to expand or add a submersible aspect, this is a good choice.

The Aquascape filter is designed to be adaptable to work with almost every type of filter thanks to a threaded intake. It can also support a pond up to 800 gallons, making it perfect for small or medium-sized ponds with fish and plants.

Once placed on the bottom of your pond, it provides mechanical filtering with a coarse sponge and biological filtering with a ceramic biodome.

The coarse filter may not catch all of the smaller particles, but it is possible to purchase a thinner material and replace it. This allows you to alter your pump to fit your needs depending on the environment fo your pond.

Also, while this is a submersible pump, it is designed in a way that is easy to remove for cleaning and maintenance.

8. SUN Grech Bio Pressure Filter

The most distinguishable feature on the SUN pressure filter is its handle design.

Most filters, especially those using a mechanical system, require you to open the system and rinse the filers. To make cleaning a breeze, this one has a unique handle to make cleaning easy – no removal involved!

It also supports both biological and mechanical filtration systems. This helps make sure that your water is as clean and healthy as possible for your fish and plants.

If desire, this filter can be combined with a UV pond filter for added benefits to make sure it’s as efficient as possible.

When it comes to support, this filter can maintain ponds with fish and plants. For mixed fish, it can support up to 900 gallons; for just plants, this number goes up to 1600 gallons.

The instructions can be difficult to understand, but the setup is simple and can be accomplished.

9. TetraPond Filtration Fountain Kit

If you’re looking for a secondary filter or just looking for a multi-beneficial fountain, then this is a great option.

It offers a mechanical filtration system with a coarse and fine filter. As a result, it catches small and large debris for cleaner, clearer water.

It also comes with three fountain heads – froth, spray, and bell-shaped. This allows you to increase your pond’s aesthetic value while adding a ripple to prevent surface buildup.

You can use the TetraPond kit in any small or medium pond ranging from 75 to 500 gallons with fish and plants. It also has an easy to clean and maintain design to save you time.

Related: Best Pond Vacuum Cleaners

10. Aquascape Pond Filter and Waterfall Spillway

Looking for a way to add a waterfall to your water feature while still helping maintain clean, clear water? The Aquascape pond filter provides biological and mechanical filtration to ponds up to 1000 gallons, making it a great choice.

It’s designed to have a positive user experience by being easy to install and maintain. It is also designed to prevent water loss to help maintain water levels in your pond.

To ensure that you are happy with your product and that it works as expected, there is a 5-year limited warranty.

Buying Guide – Everything You Need to Know to Pick the Best Pond Filtration System

What does a Pond Filtration System Do?

When you are setting up your pond filtration system, depending on the size, you may want to use two filters. This ensures that your pond is getting the optimal amount of filtration to keep it clean with healthy oxygen levels.

The first filter – your pre-filter – doesn’t impact your water as much as your filter and secondary filter (if you choose to have one). Its main job is to keep your filters running smoothly throughout large debris.

Pre-filters should be cleaned around once a week for optimal flow. Cage filters will only require debris removal while foam can be rinsed with pond or well water.

Your second filter is the main filter and deals with keeping your water clean and oxygenated. The best type of filtration to have is a mixture of mechanical and biological.

Now since you know more about how you should set up your filter for optimal care, you can learn about the three main types of pond filtrations systems.

Three Types of Pond Filters

Biological

When you use biological filtration, bacteria grows with the filter. When your water runs through the pond filtration system, it comes into contact with this bacteria.

These beneficial bacteria break down ammonia from fish waste and plant matter, which can reduce the oxygen in your water. They then recycle the ammonia into the water in the form of nitrate, a process known as the nitrogen cycle.

This process involves no chemicals or even mechanical gradients. In fact, this is how pond water is maintained in nature free of human influence.

Mechanical

Mechanical filters work by running your water through different mediums. These mediums trap and remove things such as sediment and debris from your pond water.

When certain materials, such as plant waste, are left in your pond water, they can encourage the growth of harmful algae. This can impact your water quality and even harm any fish you are growing, which is why it’s important to remove.

Sterilizers

Before we get into what exactly sterilizers are, it’s important that we help you understand a common misconception.

While sterilizers are often listed as a filtration system, they don’t actually filter your water, so they won’t clean debris. Because of this, you’ll want to have a secondary filter for any large debris or remove it by hand with a brush or net.

Instead of relying on filters, sterilizers usually use a UV light to kill any harmful algae or bacteria in the water.

UV-C radiation, which is the technical name for the type of UV light, kills algae and bacteria through a process known as ultraviolent germicidal radiation. In simple terms, this just means that UV light causes radiation damage to algae and bacteria that can harm their DNA, killing them.

This process has become extremely popular in recent years, even outside of the gardening and landscaping niche. In fact, it’s even become popular in the beauty industry!

All this means that certain UV lights are designed specifically to target microbes like algae and bacteria. They won’t harm your fish, and, unlike biofilters, they actively work to kill algae rather than just preventing growth.

What to Look for When Buying a Pond Filter

Now you know more about the different types of filters. You’ve also seen 10 different types of filters that we recommend.

Now, it’s time to learn the three things that you should look for and consider when buying a pond filter.

Durability

Whether you have an external or internal filter, it’s going to be exposed to the elements at some point. That’s why you need to make sure the filter you choose is as durable as possible.

Try to stay away from cheap plastic or materials that will corrode quickly.

You’ll also want to make sure that the filters are high quality and reusable. Good quality filters should hold up during regular washings and shouldn’t break during normal use.

Investing in quality upfront will reduce the amount you have to pay later on in replacement or repair fees.

Efficiency

The best pond filters are those that utilize more than one filtration system. Even the system – whether it’s mechanical, biological, or sterilization – has its pros and cons.

Rather than buying a filter that only supports one type of system look for a filter with more than one system. Otherwise, you may find that you have to purchase a secondary or tertiary filter just to cover regular maintenance.

A large majority of filters support both biological and mechanical filtration systems, which are a great choice, especially for beginners. Some filters even offer all three types of pond filtration systems, and these are the best as they leave no stone unturned.

Set-up

You’ll need to think about which set-up style – external or internal – best fits your pond and your lifestyle. Both styles offer pros and cons, so it’s important to do your research.

To help you understand both systems a little better, we’ve provided a short guide.

External vs. Internal Pool Filtration Systems

When you begin shopping for the best pond filter for your pond, you may notice filters are either external or internal. If you’re new to pool filtration systems, this may appear a little confusing at first, but no worries!

Both systems have their own pros and cons, and we’re here to help you navigate which one works best for you.

External filtration systems are installed outside of the pond. They’re designed for larger ponds, up to 20,000 gallons, and they are easier to maintain and setup.

Internal filtration systems, also known as submersible filters, are installed directly in the pond. They’re designed for small to medium pools, and, though they’re easier to disguise, they’re harder to access.

Here are some of the main factors to consider when picking the best pond filter for you:

Factors to Consider with External Filtration

• Harder to disguise
• Intended for larger ponds
• Easy to maintain and set up
• Often requires protection from the elements

Factors to Consider with Internal (Submersible) Filtration

• You will most likely to need to remove the device from the water to clean it
• Easier to disguise
• Intended for small to medium ponds
• More difficult to maintain and set up

FAQs

When should I clean my pond filter?

How often you should clean your pond filtration system depends on how long you have had it.

During the first six weeks of running your pond filter, it’s important to establish a routine. This involves cleaning the filter twice a week.

When you are cleaning during this time period, make sure that you are rinsing the filter in a bucket of pond water.

After six weeks, you can clean your filter once a week or as needed when the temperature is above 65 degrees. This includes if there is a large amount of plant matter, debris, or dirt stirred up in the pond.

At this point, you can rinse the filter with your garden hose. Just remember that it won’t be completely clear after cleaning, and that’s okay.

How do I keep my pond clean naturally?

Not only does algae and cloudy water look bad, but they can also be extremely harmful to your plants and fish. However, you also may not want to use potentially harsh chemical cleaners.

So, how can you find the balance between a naturally clean pond and, well, a clean pond? Thankfully, there are a few options you can try!

Barley is one of the most popular natural cleaners for ponds. In fact, there are even multiple studies detailing just how efficient it is. 

Barley only works to prevent the growth of algae. This means that it won’t kill existing algae, and it won’t work on vascular plants.

The process is actually really simple. As the barley decays, it releases a special chemical – simple to hydrogen peroxide – that prevents algae growth.

You can also mechanically clean your pond by scrubbing away growing algae and removing debris and plant matter with a net. While this isn’t the most efficient option, it will work to help keep your water clean.

Finally, another great way to keep your pond clean naturally is to use a biological pond filtration system.

Can a pond filter be too big?

While pond filters can be too small, they cannot be too big, especially if you’re relying on a biological pond filter.

Since the bacteria grow inside of your filter, the larger the pond filter is, the more bacteria it can support. Thus, bigger is actually better!

Mechanical filters work similarly by forcing the water through different mediums much like a strainer to filter out anything harmful. Since they’re designed to only remove things such as waste products, too large a size won’t have a negative impact. Do not overfeed your fish, for avoid it you can use automatic pond feeder.

Your filter can be too small, however. If this is the case, you’ll find it’s not allowing the appropriate amount of filtration to occur.

If you’re unsure of what filter your pond needs, it’s always better to go with the bigger option. You may even find that the bigger option is more beneficial!

Can you over filter a koi pond?

It is more harmful to under filter than it is to over filter.

In the wild, fish do not swim in crystal clear water. However, that does not mean swimming in clear water is harmful.

Using a larger pond filtration system or a secondary filter means you’ll remove more debris from your koi fish’s water

This is in no way harmful to your koi pond.

Too little filtration, however, can result in poor water conditions and sickly koi fish. Thus, since over filtration isn’t a concern, it’s better to have more than you need than not enough.

And this applies to all three types of filtration!

With biological filtration, the water is being run through colonies of bacteria to remove harmful ammonia and turn it into oxygen. This means that, since all you’re doing is oxygenating the water, there’s no way to overdo it!

In fact, more is better, especially during certain parts of the day!

With mechanical filtration, you’re running your pond water through different mediums that filter out large debris and algae. Algae offer no benefits to your fish, so removing all of it is in no way dangerous.

Finally, UV pond filters are designed in a way that they will not hurt your fish. So, you can use it 24/7 and not worry!

Does a pond filter need to be on all the time?

The best way to answer this question is to think about why you use a water filter for your fish pond. While filters can help with the general clarity of the water, they have another significant job as well.

As mentioned above, the main purpose of a pond filtration system is to remove ammonia from the water. When it is recycled into nitrate, this adds oxygen to the water.

This means that what your filter is actually doing is oxygenating the water for your fish and plants. The more time that your filter is off, the more potentially harmful gases can build up.

So what does this mean for you?

Well, first, you should aim to keep your filter on as much as possible – 24/7 is ideal. Filtration is especially important in the morning when oxygen is at its lowest in the water.

With biological filtration, a constant power supply is even more important.

The bacteria growing within the filter require water. Even 8 hours without power can cause damage in your bacteria colony that can take weeks to repair.