Last Updated on June 19, 2025 by Tanya Janse van Rensburg
Aeration plays a vital role in keeping the health of fish and plant life in ponds. Without it, ponds become stratified, generally with the warmest layers on the top and the coldest layers on the bottom.
When there's no water movement, oxygen can't enter the pond effectively. Without oxygen, fish will die, the water will start to smell, and there will be an excess of algae and pond muck.
To get the water circulating, you can use floating fountains or pond aerators.
A floating fountain is the most visually appealing option; it creates a beautiful display as water cascades over the surface, and the gentle sound adds a calming ambience.
A pond aerator, on the other hand, is more functional when it comes to moving larger volumes of water. It circulates water from the bottom up, helping oxygenate the entire pond more effectively.
To help you decide which option would be more beneficial for your pond, let's take a closer look at both of them.
You will find a range of floating fountain designs available, but most of them will include a pump, nozzle, floating base, and power supply.
The pump draws water from the surrounding body of water and pushes it upward through the nozzle, where it is expelled.
Different nozzle designs can create different spray patterns, such as jets, sprays, or mists.
The process of pumping water into the air and allowing it to fall back helps increase water circulation in the pond while creating a visually appealing effect.
When it comes to installation, it's pretty much a straightforward process. The fountain is typically mounted on a buoyant platform that keeps it afloat.
It can be powered by electricity, which can be supplied through a cord leading back to a power source on land or through solar panels.
Although pond fountains are great for providing surface aeration, they often don't supply sufficient oxygen at deeper levels to support healthy aquatic life.
To get oxygen moving to the deep water layers of the pond, you would need to invest in pumps with higher flow rates and great pressure.
Aerators work by pulling in air and spraying out small drops of water. As these drops rise, they bring water from the bottom up and mix it with the oxygen-rich water at the surface.
This movement adds more oxygen to the pond, helping keep fish and plants healthy and the water cleaner.
One benefit that aerators have over fountains is that they can circulate larger volumes of water. They are also better suited for use in very hot climates, when oxygen levels in ponds can plummet.
However, aerators must be used above a certain temperature to ensure top performance and safety.
This temperature is usually 17 °C. Using an aerator in a pond where the water is below this temperature could cause fish to stop eating.
It's also important to note that the installation process of a pond aerator is generally more complicated, and a professional may be needed.
The pump must be safely fixed underwater and powered by electricity, which requires adequate wiring to an electrical outlet. Plumbing is also often necessary to ensure the entire system works correctly.
Choosing the right fountain size is important to achieve the desired performance and visual effect. As mentioned above, fountains are available in a range of sizes, typically measured by horsepower (HP).
The size of your pond will help you decide with fountain size is most suitable.
Larger ponds will need more powerful fountains, such as 3HP, to create proper aeration and an impressive display. For a smaller one, a fountain with 1/2HP or 1HP may be enough.
The depth of the water is another important factor to consider. For ponds deeper than 2 meters, an aerator might be a more effective option.
If your pond is deep and you also want to enhance its appearance, you might consider using both a fountain for visual appeal and an aerator to ensure proper oxygen circulation.
If you're looking for a tall, majestic spray of water, then you'll need to get a fountain with higher horsepower.
But to reach significant heights, the fountain will also need to include a nozzle featuring smaller holes. Smaller holes restrict the flow of water, allowing less aeration than larger holes.
As with fountains, choosing the right size of the pond aerator is also essential. Overaeration can impact the pond's natural balance and harm aquatic life, just as low oxygen levels can.
To determine the correct aerator capacity, it's important to accurately measure both the surface area and the average depth of your pond.
These measurements help ensure the system provides effective and balanced aeration tailored to your pond’s specific needs.
Choosing models with adjustable settings or timers gives you the flexibility to control when and how long your aerator runs.
For example, during colder months or when the pond is less active, you might reduce aeration to save energy. Conversely, during hot summer days, increasing aeration can help prevent oxygen depletion.
By setting specific schedules or adjusting the power levels, you can optimise oxygen levels in the pond according to seasonal changes or weather conditions, ensuring the pond remains healthy and energy-efficient throughout the year.
Energy efficiency is an important aspect, as more efficient models can help reduce ongoing operating costs. One of the most energy-efficient options you can get is a solar-powered aerator.
This type of aerator can be especially beneficial for remote ponds with limited or no access to electricity.
Provided that the system receives enough sunlight exposure, it can be installed virtually anywhere. Once installed, the system will run 100% on renewable energy, resulting in zero operation costs.
If the pond is in a backyard or near outdoor seating, a noisy aerator could ruin the peaceful ambience.
To choose a pond aerator with quiet operation, check its decibel ratings to compare noise levels. Also, look for units with rubber-mounted components or noise-dampening enclosures.
