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Pond care in summer: how to take care of your garden pond by following these practical tips

Like the garden area, you need to maintain your garden pond and clean it regularly to keep animals and plants thriving healthily. If you don’t have a pump or filtration system installed, you will need to keep the water clean yourself in the summer through proper pond care. Glorious sunshine is usually pleasant for humans, but can be a real challenge for fish and pond plants due to the heat. In addition, garden ponds need a little extra care during heat waves to ensure the health of the plant and animal life that is attracted to them. When water temperatures stay above 26 degrees during the summer, it’s important to take the right steps. Here is some advice and information that can help you with summer pond care.

How you should care for a garden pond when temperatures are high

proper pond care in summer allows plants to thrive healthily

All ponds green up a bit when the water warms up, but if the balance is right, this will clear up quickly. Removing seed heads, for example, can help reduce weeds and thinning in the future. Avoid spring maintenance activities when you may inadvertently remove tadpoles and other aquatic larvae and eggs from the pond.

care for potted plants at the bottom of a garden pond and remove weeds properly

It is also worth leaving removed vegetation next to the pond for a few hours to allow invertebrates hiding in it to re-enter the water. Check the leaves for eggs and return any you find to the pond. On long summer days or extreme heat waves, depending on where you live in the world, a garden pond is prone to an increase in photosynthesis. This causes rapid water evaporation and faster growth of algae or filamentous algae.

koi fish in pond looking for oxygen during high temperatures in summer

Aside from that, there is the inevitable warmer water temperature, which is more dangerous than many people think. As water temperature rises, it loses its ability to hold oxygen, making it harder for fish to breathe. However, as dramatic as this may sound, there is no need to panic. There are some quick and easy changes you can make to ensure you are maintaining your backyard pond as effectively as possible during the summer. This will keep your fish fit, healthy, happy and well during the hot months. So, discover some useful tips for summer pond maintenance below.

Regularly fill up the pond with water during the summer time.

regularly refill water with a vessel in summer and maintain the garden pond with more oxygen


Fill up your garden pond with water using a plastic container or bucket. Add more water as it evaporates in the summer and the level drops. When doing this, ideally use rainwater from a barrel about once a week or as needed. If you only have tap water available, let it sit for 24 hours before adding it to the pond. This will allow any harmful chemicals like chlorine to evaporate.

pond fish swim in polluted water because of the lack of a filtration system

You may think this seems like a strange suggestion, but as temperatures rise, this means water evaporation will increase rapidly. For example, if there has been very little rainfall for a few weeks, your pond may be leaking. In addition, keeping your pond full is absolutely essential to the health and life of your pond fish.

Monitor the behavior of the pond fish

feeding koi fish in a pond during warm weather


Keep an eye on your fish population when maintaining your backyard pond. Do your finned friends seem stressed, gasping for air near the water’s surface or especially near a fountain or waterfall? Warm water has a low oxygen-holding capacity, while cooler water can hold very large amounts of oxygen. In addition, warm pond water and increased fish activity go hand in hand. In fact, this increased activity means that your fish need more oxygen. This creates a vicious cycle, whereby stressed fish often begin to develop diseases, and soon a domino effect occurs.

maintain a solar fountain or solar powered water feature in the garden pond

So if you haven’t already, add oxygen to your pond by installing an aerator or pump. You can also use this in the winter by having a hole in the ice. You can even install a solar powered fountain and pump if your pond doesn’t have a waterfall or stream. Make sure all areas of the pond are skimmed and the water is circulated. Also, remember that waterfalls, streams and even water fountains play a big role in oxygenating the water in your pond.

Remove algae and decaying vegetation, as well as eliminate pests.

remove rotting vegetation from the water in the garden pond and improve pond maintenance in summer

Remove rotting vegetation, including old lily pads, which can increase nitrogen levels and turn the water green, while a layer of sediment forms at the bottom that can cause an odor. Also, do not leave dead or dying foliage in the garden pond.

remove thread algae and other duckweed from garden pond in summer

Filamentous algae, which can spread quickly and smother a pond, should also be removed during the summer. Do it by hand or use a pipe by twisting it around and then remove the smaller pieces with a net. Duckweed can also overgrow in a pond and should be removed by hand.

control small bugs and pests in the garden and maintain a garden pond

Some beetles can infest water lilies in the summer. The larvae of these beetles attack the leaves from the inside, causing the leaves to turn brown and die quickly. The only solution is to regularly prune and remove the affected leaves. The earlier and more consistently you do this, the fewer problems with pests you will have. In the summer, a lot of pollen and other dust will also be blown into your pond. Therefore, keep the water surface clear with a special tool. Make sure the KH or carbonate hardness stays high enough during this time. This will keep the water crystal clear and prevent algae growth. The KH value determines the capacity of acid neutralization, which is important for the growth of oxygen plants. This value can be determined with special tests.

Remove excess aquatic plants and weeds.

too many oxigenating aquatic plants like hornwort can affect a garden pond in summer

Reduce the volume of pond plants such as a hornwort if they fill more than one-third of the pond. These are essential to ponds and keep the water clean, but they need to be kept from taking over. Weed between marginal plants, such as weeds, as you would in the garden. Be sure to remove any unwanted seedlings as you maintain your garden pond. Sometimes it’s easier to remove the pot they’re growing in, then divide the border and replant before putting it back in the water.

Brave the late summer heat and maintain your garden pond

care for rotten water lilies in a garden pond and remove dead leaves

There are some preventative measures you can take to keep your pond from turning into a warm, unhealthy puddle at the end of summer. It all starts with a well-designed water feature. Water depth, plant cover, shade and circulation should all be considered accordingly when designing and building a garden pond. A minimum depth of 0.5 meters is recommended here to keep the pond bottom cooler.

duckweed-covered water surface of a pond during the summer season

You should stock your pond with plenty of plants to provide shade for the fish. A good rule of thumb is to have plant coverage of about 1/3 to 1/2 of the water surface. Consider adding floating plants such as water lettuce and water hyacinth, although you don’t necessarily need to pot or plant them. Circulation is also important, and you should place a biological filter and a mechanical filter across from each other to give your pond optimal circulation. Last but not least, you can help keep your pond functioning optimally during the last months of summer with these tips:

  • Feed fish in the morning and be mindful of the amount of food you feed. Leftover food will decompose faster in warmer water and can pollute the pond.
  • Be sure to remove dying leaves and flowers before they can rot in the warmer water.
  • The bottom line is to continue to keep an eye on your pond and let your fish and plants do the talking. If you have a balanced ecosystem, it will be much easier for you to maintain the health of your pond, fish and plants. Not to mention, it will help you make a healthy transition into the fall season.