We are often attracted to the idea of having a mini pond in our garden with fishes or plants or just some decorative pieces. But in that excitement we forget to factor in the cleaning of the pond. If you are planning to get a pond, you need to think of various things like its appearance and its size. All these choices will then lead you to what kind of pond filter you may need.
You have seen natural ponds thrive well without artificial cleaning, but that does not happen in case of man-made ponds. The latter require artificial aeration, and a system wherein the waste produced by the fish in the pond can be removed. If there is no aeration, the fish will not survive.
If there is no system to remove this waste, there will be growth of bacteria and algae in the pond. The water will turn a greenish shade and your pond will stink. It will become a breeding ground for mosquitoes and other unwanted elements.
So, any man-made pond has to have a system of filtration and aeration. Most filtration systems these days come with an ultraviolet steriliser to kill the algae. The UV steriliser is used in conjunction with the filter.
Features to Look for in a Pond Filter
Before you set out to look at various filters, you need to know what features you will be ticking off the list and what are the factors you should consider...
Type of Filter
Mechanical Filters - Mechanical filters are used to get rid of physical debris or particles that may block the flow of water. This filtration is required to keep your pond water clean and safe to use. These filters clear the leaves, stirred-up mulch or free floating algae, preventing clogging of other pond equipment. This is done by straining the water through different filtration media of varying densities and thicknesses.
Biological Filters - Biological substances present in the water give rise to algae production that depletes the oxygen supply in the water, ultimately leading to the death of fish in the water. This is caused due to a build-up of a harmful level of ammonia in the water. The biological filters get rid of excess ammonia using nature’s nitrogen cycle to detoxify organic waste.
UV Clarifiers – These are standalone units that are often combined with biological filters, and its purpose is to filter the green water and reduce the harmful bacteria in it before it enters the biological filters. It clumps together single cell algae which can be easily broken down by the biological filter, effectively eliminating green water.
Chemical Filters - This filter is optional. It removes organic and inorganic substances from the water using special filtration media like carbon and resin. The pollutants tend to stick to them and are then removed.
It is an important component of a good filtration system; however, it may or may not come along with the filter. The pump is what will circulate the water through the filters. It is important to have an effective pump because that will ensure that all the water is pumped through the filter for the necessary filtration process to take place. The pump size, pressure and volume are important things to note.
- Pump pressure is how quickly the water is circulated.
- Volume is how much water is circulated.
- The pump needs to circulate water through the filter for 60 to 90 minutes. Example if your pond is 500 gallons, then a pump should be rated in between 5 to 8 GPM (500/60=8 and 500/90=5)
- The volume of the pond can be determined by the formula-Length * Width * Height of the pond. Divide the result with 231 to arrive at the number of gallons (if measuring in inches).
External vs. Submersible
A submersible filter is hidden completely inside the pond with one end connected to the pump. They can be tough to clean. External filters are placed somewhere on the land and are hence not submerged.
What is the Best Pond Filter?
Below we have gathered together information on some of the most popular pond filters around...
TetraPond Submersible Flat Box Filter – Flexible and Cost-Effective
Following are included with the package: -
Filter box to foam filter pads, as well as tubing, filter to hose fittings, and tubing fittings for connecting to the pump.
This is a mechanical filter that clears the pond of all dirt and debris and prevents the pump and fountain head from clogging. It can be used for ponds with a volume up to 500 gallons.
Since it is a submersible pond filter, one needs to insert it into the water till it is fully submerged and all the air has been removed when installing.
One of the best features of this product is that it can fit a wide variety of pumps ranging from 200 to 2000 gph. No hose clamps are required to connect to the pump- the fittings and the tubing serve the purpose well. This filter is ideal for medium sized pre-formed ponds.
The product is an easy-to-install, budget-friendly filtration kit that employs both coarse and fine mechanical filter pads to effectively strain the waste products from the pond water. Also, old and worn out filter pads should be replaced from time to time.
It comes with 1-year warranty.
Pondmaster PMK190 190gph Pump and Filter – Easy-to-Use Filter with Integrated Fountain Head
Made of plastic, the filter comes in a package with the following: 190gph pump, filter, fountain head and a 10-foot cord.
This kit contains a pump, filter and a nozzle which makes it very efficient. It is an excellent kit to connect a pond filter to a pump and or a fountain-head in cases of small ponds. So it is very convenient for a first time user.
This filter provides both mechanical and biological filtration, so both the fish and the plants are managed. It is a fully submergible and can be used for smaller ponds ranging up to 200 gallons. Only when the unit is completely submerged will it operate quietly, else it will hum and buzz.
The pump moves 190 gallon of water per hour, helping to sustain healthy plant and animal life and also creating pleasant ripples in the water. While the mechanical filter prevents clogging, the biological filter converts harmful pathogens to useful nitrates, promoting plant growth.
This product comes with a 15-year limited warranty on the liner and 2-year limited warranty on the other components.
TetraPond Filtration Fountain Kit – 2 in 1 Filter and Water Fountain Kit
The kit comes in 3 sizes:
• 50 to 100 gallons
• Under 100 gallons
• 250 to 500 gallons
The package includes a 325 to550 gph pump depending on the size, a pre-filter, flat box filter, fountain attachments (frothy, spray and bell), diverter assembly, tubing and other fittings for installation. The 50-250 gallons filter is considered an ideal fit for medium sized pre-formed ponds. The best part is that it is a 2 in 1 filter and water fountain kit.
It is a mechanical filter that keeps the pond clean by straining physical material from clogging the pump and fountain head. The flat box submergible filter uses coarse and fine filter pads to trap debris from the pond water. You need to get the hang of how to handle various components so that they function the way they should. For example, you need to hold the flat box under water so that water fills in and the box settles down, rather than floating on the surface. This product has an added fountain head attachment.
Make sure that you use the right capacity pump for the size of the filter; else you won’t get the desired effect of the fountain head. The product comes with a 3-year limited warranty.
Best Choice Products 4000 Litre Pressure Bio Filter with Uv Sterilizer Light – Biological Filter with Integrated UVC
It works for ponds of up to 2500 gallons capacity.
The package comes with a CPH-180 pressure filter, with integrated UV clarifier, spiral stepped hose adapters, bio balls, and multi-directional valve for cleaning.
This is a pond pressure bio filter with an integrated UV clarifier and a UV lamp indicator which makes it both efficient and effective. Bio filters clear the pond water of organic waste and the UV clarifiers further help in filtration by eliminating bacteria presence in the water. This filter has been designed to filter up to 12000 litres of water. It is an external filter and should not be submerged in water.
This is an easy to use product that comes with all its parts ready to install making it easier to maintain. The flow indicator on the filter indicates when the filter needs cleaning. It is also very easy to wash the filter sponges.
One thing to note is that it does not include a pump. You need to look at the pump requirements and purchase it separately.
Jebao CF-10 Pressured Pond Bio Filter with 13W UVC Clarifier – Dual Filtration Mechanism
This product comes in a variety of sizes depending on the size of the pond, which can range from up to 1000 gallons to 4000 gallons.
It comes with an integrated 13W UV Clarifier, backwash facility, cleaning indicator and a UVC viewing window. The product description below is for the filter that is suitable for up to 1000 gallons. It is recommended that you use it with a pump of 850-1250 gallons of water per hour pumping capability.
This filter also has both a mechanical and a biological filter. In the first stage of filtration, two foam filters collect various sizes of debris (mechanical filtration). The second stage is of biological filtration where the water passes through bio balls that convert harmful ammonia into nitrates to help promote healthy plant growth. This is followed by the UV clarification process that kills traces of bacteria and spores in the water giving birth to crystal clear water.
This dual filtration mechanism makes it an extremely effective filter, however it is an expensive purchase.
TetraPond Bio-Active Pressure Filter – Expensive, without UV Clarifier, Yet Effective
The pump does not come with the pack. This filter is good for ponds accommodating up to 1500 gallons of water.
It provides both mechanical and biological filtration, which takes care of the general waste materials in the pond. The good thing is that it offers black flush valve, which reverses the direction of water flow for the purpose of cleaning the bio-activator chamber. The water current that is created because of this reverse direction loosens the debris accumulated on the bio-activators. Because of the backflush system, it is important that you choose the right pump. The pump should be able to circulate a minimum of 2500 gallons per hour.
The bio-activators in this filter provide a large area for beneficial bacteria to grow which means better cleaning. As you know, these good bacteria are important in the filtration process.
One drawback of this system is that it does not have a UV clarifier, despite the price being on the higher side. The UV clarifier usually kills the algae and harmful bacteria, which are then removed by the mechanical filtration process. Due to the absence, the water is not sterilised.
However, the mechanical and biological filters do their job well. This filter comes with a 2-year limited warranty.
TotalPond Complete Pond Filter with UV Clarifier - Effective Appliance with UV Clarifier
The package comes with a course filter, fine filter, bio-balls, and 9 watts UV Clarifier.
You can use a pump of 550-1200 gph, depending on the size of your pond. The filter is suitable for a capacity of up to 1200 gallons.
The filter has a pressurised biological filtration system with a UV clarifier. The water is forced through 2 filters (coarse and fine filters) which remove the solid waste after which it passes through bio-balls where the good bacteria are segregated. Natural bacteria can create a healthy pond. The UV clarifier is an essential add-on, as it removes the bacteria that will lead to algae. This ensures that your pond water does not become green over a period.
A common issue with this filter is that it leaks. If you can tackle it, well and good. You can place the filter either outside or inside the pond- it can be used as both an external or a submersible filter. Leaks will be obvious in the former situation, while in the latter case it could affect the water in the pond.
The UV clarifier adds to the cost. Hence this filter is a little expensive.
TetraPond Bio-Active Pressure Filter with UV Clarifier – Suitable for Large Ponds
It requires a pump of at least 2500 gph for the backflush operation to function properly. You can use this filter with a pond of capacity up to 4000 gallons. So looking at the dimensions and the capacity, this is suitable for larger ponds.
The package includes a UV bulb, but not the pump.
The mechanical and biological filters work with the integrated UV clarifier. The bio-activators provide a large surface area for cleaning water. In the first step of cleaning, water is cleaned by the filters and then the water is forced up the centre tube where the UV light kills the single-celled algae. This dead alga is then removed by the bio-activators.
The UV bulb will have to be replaced once in 9 months or so.
The system has a backflush valve for cleaning the bio-activators. However, there are issues with the backflush wherein users have to manually remove the accumulated algae.
The price is quite high considering the UV clarifier and the size of the pond it caters to. So invest in it only if you need a high capacity filter.
The filter has a 2-year warranty.
Aquascape 95110 Submersible Pond Water Filter – Convenient Design, Easy Cleaning
The filter is suitable for ponds containing up to 800 gallons of water. So, if you have a medium sized pond you can consider this filter.
The package includes the filter only. You need to buy the pump and tubing separately. There are no specific pump capacity requirements.
While the filter provides mechanical and biological filtration, it does not provide UV clarification. The filter is designed such as that its outer cage can be easily removed for cleaning. It is circular in shape and quite easy to handle and maintain. The outer cage filters out large debris.
There is also a pre-filtration sponge for the mechanical and biological filtration. Inside, it has ceramic filter rings to assist the latter.
The price is quite reasonable. The only thing that might hold you back with this one is that it is quite simplistic in its design. If you are not looking for anything elaborate in your filter and still want effective results, you can opt for this one.
Overall, it is effective for small to medium sized ponds.
Laguna Pressure Flo-Clean 1400 Pressurized Pond Filter for Ponds Up to 1400-Gallon – Easy Handling with Click-Fit Connectors
The package includes lava rock bio media and click-fit fast couplings for ¾-inch, 1-inch and 1 ¼-inch hosing.
This filter is ideal for ponds with capacity up to 1400 gallons. It is designed to work with Laguna’s Max-Flo pump. This will restrict your options, especially if you were planning to use this filter with a pump you already have. However, it is only a recommendation and you can check with them if you can use any other pump.
It has mechanical and biological filtration systems but lacks a UV clarifier. The systems are effective in keeping the water clean and clear. The installation process is quick and easy because of the click-fit connectors.
The filter has a backwash system using which you can clean the filter without opening it. There is a cleaning indicator to tell you when to perform the backwash.
It comes with a 3-year warranty.The price is on the higher side, which is surprising because the filter does not come with UV clarifier. This product also has issues such as leaking.