Ecosystem PondsMaintenanceSummer Pond Care In Southern Oregon

July 3, 2023by Bill Seeds

Looking for summer pond care tips in Southern Oregon? Specifically the Grants Pass, Medford, Ashland, or Roseburg metro areas? Then this article should help you with caring for your pond during the summer.

We will cover topics like the heat, fish health, algae control, and ways to care for your pond during the dog days of summer.

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First and foremost, if you have fish, koi or goldfish, it is important to know their ideal temperatures. Their optimal water temperature is between 60 degrees F and 75 degrees F. So if you do not have a thermometer I recommend getting one as soon as possible. They are relatively inexpensive. They can also help you determine when you can feed your fish starting in the spring and when to stop in the fall. I recommend feeding after water temperatures are above 55 F.

In the Rogue Valley, we can experience long weeks of 90+ temperatures during the day consistently with long dry spells. Luckily, our nighttime temps are in the low 60s and 50s, so relief is available for your fishy friends. Sometimes these temperature swings can be just as harmful to your fish though.

This is why we do not recommend cleanouts to our fish pond customers during hot summer days. There is too much risk to the fish. And if you are determined to do water changes make sure you are slowly acclimating your fish to your well water so you do not shock them. Temperature differences of 10 degrees can be deadly in some cases, especially with our high ph and hard water.

High fish loads to water volume can also have poor effects on their health. More fish equals more waste, less oxygen, and poor pond health.

I will cover Oxygen and Shade in the next paragraphs.


The heat can bring stress to your fish. But it isn’t just because of the temperature. Warm water holds less oxygen than colder water. So it is imperative that you have a functioning waterfall or some kind of aeration. Don’t think of the waterfall or aeration as adding in oxygen. Think of it like you are creating more surface area for gas exchange.

At the top of the water nitrogen is escaping, and oxygen is coming into the water. We call this the gas exchange. This is why during the winter time you need to keep a hole open in the ice so that your fish can breath.

Typically with a waterfall and properly sized pump, you will be oxygenating your pond sufficiently. But if you want to supercharge your biological filter, and have a redundancy for your fish, adding in an aerator is great way to improve your pond and oxygen capacity. Depending on your pond depth, you will want to put the aerator on a top shelf close to your skimmer. As long as your pond is 2 feet deep your fish will be fine.


Some ponds are in direct sunlight. If your pond gets sun more than 8 hours a day, then you should consider a shade component. Fish can get sun burned! If you do not have a fish cave or hideout then I would seriously consider installing one or adding in a shade component. There are shade cloths, umbrellas, or even plants that can accomplish this.

If your pond is very large, and or deep, then you can probably exclude some of this advice since a larger body of water has a more consistent temperature due to thermal dynamics.


If you read any of my other articles, or have seen my pond builds, then you will know I am a BIG plant guy. Waterlillies are an exceptional plant that will give your pond a lot of shade. And they love the heat. As long as they are properly planted in large pots with adequate soil and fertilized in the spring they will do wonderfully.

Frogbit, water lettuce, and hyacinth are also excellent shade producing plants that will propagate easily. Unfortunately, you have to treat them as annuals since they are tropical plants, and will die once the weather reaches 50 F. Here are some other native plants I recommend.

One thing to remember with plants is that you must have a balance, just like your fish load. Too many plants can also have a negative effect on the oxygen carrying capacity of the water. Plants absorb carbon dioxide and release oxygen during the day. But at night they absorb oxygen. If the weather is too warm, they can deplete your oxygen at night, especially if you have a high fish load. Less oxygen means less bacteria. Less bacteria means more ammonia. And with our high ph water that is almost certain death for your fish.

I recommend a 30% coverage of your pond surface in aquatic plants maximum. There are exceptions to this rule such as having a larger/deeper body of water, and or having a constructed wetland filter with plants.


If you are having algae problems do not ever use algicide. Especially in the summer months. Algicide might kill algae, but it consumes a lot of oxygen. It also leaves the dead algae in the pond which feeds the next algae bloom. You need to fight the cause of the problem, not the symptoms. And your expectations for algae should be within an exceptable range. Algae is part of the ecosystem. We want some algae on the rocks and surfaces of the pond, but not in excess, like string algae, or green water.

Algae problems are a symptom of either lack of filtration, improper water circulation, or lack of aeration. I group biological filtration and plant load into the same category. If you have proper biological filtration, then consider adding in more plants. Make sure you continue with your beneficial bacteria treatments a weekly, or even twice weekly basis. If you have proper filtration, check and make sure your pump is circulating the water properly with no dead areas in the pond. Consider adding in an aerator where dead spots occur to help move the water. Learn more about how Ecosystem Ponds work here.

Hopefully this article has helped you understand how to care for your pond in southern oregon during the summer. Please do not hesistate to reach out for help with your pond.

Check out our latest youtube video of a waterfall build into a recreational swim pond!
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