Last Updated on January 5, 2020 by Aiden Lindow

How To Keep Your Pond Cool In The Summer

In this guide, you’ll learn exactly how to keep your pond cool in the summer. Your pond can get warm quite fast during the summer and that’s why you need to be prepared.How To Keep Your Pond Cool In The Summer

When the temperature increases in your pond it can cause a decrease in oxygen, you will see fish very close to the water surface gasping for breath, usually near a waterfall to maximize their oxygen intake.

By following these steps you will ensure the cooling of your pond and create a healthy environment for your fish in the hot summer.



When getting ready for the hot summer months make sure you have plenty of shade.

The easiest way to drop the temperature in your pond is to block out the harmful UV rays that pound onto your pond from the sun.

Waterlilies, duckweed, and pond lettuce are the best plants to do this, all of these plants have large circular shaped leaves that block the sun from warming up the pond.

Another benefit of adding these plants is the oxygen they will produce for your fish down below.

Another way to provide shade to your pond is by using a small porch umbrella or shade covering to block out the afternoon sun.

The most important time to blackout the sun is between the times of two in the afternoon and six in the evening.


Pond Aeration

How To Keep Your Pond Cool In The Summer

In the summer months as the water heats up, oxygen levels will begin to rise which can lead to the death of your fish and other aquatic plants.

Many people believe that adding in plants is enough to aerate your pond which is true in the day time but at night the opposite happens, the plants become in competition with the fish to absorb oxygen and breathe oxygen.

Waterfalls are one of the best choices to make when keeping your pond cool during the summer months.

Waterfalls filter the water and add a nice feature to your pond, they also help with gas exchange and inject oxygen into the water.

When the water flowing out of the waterfall comes in contact with the air it becomes a lot cooler and makes the pond stay at constant levels if you have good circulation in your pond. I’ve written an article about getting more water flow from a pond waterfall if you’re interested.

That is why adding in a small fountain or waterfall is very important in providing the oxygen need for both the fish and the plants.

The less oxygen in your pond the more important factors of your pond will die such as beneficial bacteria.

If the beneficial bacteria in your pond die it will cause spikes in ammonia levels which is the last thing you want in your pond. 


Water Circulation

Circulating water is very important to keep your pond clean as well as keeping it cool.

Having stagnant water or a very low flow to your pond makes it very easy for it to become overheated.

By making sure all the water is being circulated and pushed through the fountain will make your pond cooler, and will keep your fish happy and healthy.

Another easy way to circulate your water is to add a small jet into your pond pushing the water from the far side into the pump.

You can also purchase an inexpensive bubbler to move the water around helping to make it less stagnant.


Overfeeding Fish

How To Keep Your Pond Cool In The Summer

When feeding your fish during the summer months, try and decrease their intake of fish food.

When you overfeed your fish, the uneaten food causes faster decay in warmer water which leads to ample amounts of ammonia and this will eventually kill your fish.

I recommend every pond owner purchase a water testing kit, as this will test the ammonia, nitrates, nitrites, phosphates, and pH levels.

You now don’t have to worry about overfeeding or anything because you’ll know well in advance when something is beginning to go wrong.

During the summer all of your plants and beneficial bacteria are working overtime on producing oxygen and making food for themselves which is why it is hard for them to also be filter the water and keeping it clean.

When feeding your fish, once a day is perfect. Most fish take around 18-25 hours to completely digest each meal.

Because it is during the summer, you don’t have to feed your fish so much because they will eat the algae that is accumulating in your pond.


Cleaning Your Pond

During the summer, leaves and flowers start to die and fall into your pond.

Make sure to remove them as they will decay much faster in your pond than any other time in the year.

If you’re like me and don’t like fishing out all the leaves you can install a pond skimmer. I’ve written a complete guide on the Laguna pt495 pond skimmer.

During the summer, algae is much more prone to grow as well as all of the other plants in your pond because of the increase in sunlight.

Be careful not to let the plants and algae take over as they can do this in a very short time frame.


Make Sure Your Pond Is Deep Enough

Water depth in your pond is something people often take lightly.

But if your pond is too shallow, especially during the summer months you will receive too much sunlight which will heat your pond as well as produce excessive vegetation growth.

You also have to worry about your pond drying up during the hot days because even a few inches of water taken off the level of your pond can become a big problem.

Now, if your pond is too deep, the fish won’t swim down that far because there is a minimal amount of oxygen, this happens when your pond reaches around 6ft.

Finding a balance between these two areas is key for maintaining a healthy amount of oxygen, water temperature, and vegetation.

A simple solution for this is to add a minimum of three layers to your pond, this will give your fish options to choose where they feel the most comfortable.


Do Frequent Water Changes Adding In Cool Water

Make sure when the summer months start to creep in, the water temperature in your pond does not surpass 80 degrees, once it is near and over 80 degrees it becomes very harmful to the fish living in the pond.

Doing water changes during the summer should be a ritual happening almost every day.

By adding fresh cool water insures your water will never become too hot for your fish, it also adds fresh oxygen for everything in your pond.


Add Ice

If you live in any of the southern states you know how hot it can get in the summers. It can reach that same temperature in the north with a heat spike, and sometimes, you cant prevent your pond from overheating.

A simple and very cheap way to cool off your pond is to freeze a gallon or half-gallon carton of water to put into your pond.

I know it sounds weird but it will really help. When putting in the carton of ice make sure you put it in a part of your pond that has a high flow rate so all of the water will be circulated around it.

I recommend putting it just under the waterfall or even in the skimmer box, that is where I have found it most effective.

If the temperatures where you are extremely high you might have to change out the carton of ice two or three times.



All in all, the summer months can be tough to handle for your pond, but if you are prepared, it should not be a problem.

Just doing the minimal amount to help your pond will make a giant impact on the temperature of your pond and the health of your fish.

You should not be spending hundreds of dollars to keep your pond cool and clean during the summer, all you have to do is follow these easy steps.