What Does Aeration Do to Water?

What Does Aeration Do to Water?

If you have a pond in your outdoor space you may have heard of aeration. But do you actually know what it is? What does the process do to water? What is its purpose and do you need it for your pond? Most importantly, how do you tell if you need it? Let's take a closer look at the aerating process. Once you understand what it does to water you can better decide if your pond needs it.


Oxygen in the Water

Did you know that water breathes? Of course, it doesn't have lungs so it doesn't breathe in the same sense that we do. But water needs to absorb oxygen and have the ability to release carbon dioxide and other gases. If this gas exchange doesn't happen the water gets murky, stinky, and becomes rather gross. In water that is still, the only place for this exchange to happen is on the surface. Think about how many water molecules are on the surface of your pond in comparison to the whole pond. That's a big ratio, right? The gas exchange that happens on the relatively tiny amount of surface area is not enough. Oxygen cannot travel throughout the rest of the pond fast enough. If you have fish in your pond, there is an even greater need for oxygen in the water. The blood cells of a fish need oxygen to survive just as much as ours do. If there is not enough oxygen in your pond, your fish could die. Instead of using lungs, fish breathe by using their gills to extract oxygen directly from the water. If the water doesn't have much oxygen in it, the fish will begin to suffocate. Keep an eye on your pond. If the water is lacking oxygen, you may notice fish coming to the surface frequently to gulp air. Your fish may even start to die if the problem becomes severe enough.


Anaerobic Bacteria

Another factor that contributes to the dirtiness of your water is anaerobic bacteria. Anaerobic means without oxygen. This bacteria lives at the bottom of pond water where there is little to no oxygen. These bacteria chow down on organic matter (dead leaves and other debris) in your pond. As it breaks the organic matter down it releases hydrogen sulfide into the water. This is another gas, like carbon dioxide, that the water needs to release into the air. If you don't do anything about it, anaerobic bacteria will have a party at the bottom of your pond. This will create a septic condition very fast. That is a nasty state that you want to avoid.


Underwater Plants

Did you pay attention in science class? If you did, you know that plants take in carbon dioxide and release oxygen. With that in mind, it stands to reason that plants could oxygenate the water. In reality, plants can help but are not a complete solution. Let's look at why. Floating plants can add a small amount of oxygen to the water. The problem is that they also decrease the surface area of your pond. It is far more efficient for water to have air contact so this negates the plant's oxygen benefit. Your water lilies may be pretty, but they could also be suffocating your fish. What about underwater plants? That will take care of the surface area issue. While that is true, there is one other very important piece of the puzzle. Plants only produce oxygen while they are photosynthesizing. When the lights go out, those plants are no longer contributing oxygen. But they don't stop needing oxygen. Many plants store enough oxygen within their own cells to get them through the night. But they don't produce enough of an excess during the day to adequately oxygenate the water.


This is where aeration comes in. Simply put, aeration is the circulation of air through your pond water using the aerator pump. Aeration ensures that plenty of your pond water comes into contact with the air. When this happens, enough gas exchange can take place. Byproduct gases like carbon dioxide and hydrogen sulfide have a way to get out. They don't stay trapped in there causing odors and other ickiness. This helps your pond water to stay cleaner and fresher.

How to Aerate

To aerate your pond, you need to create movement. This will ensure that more water molecules spend time exposed to the air. There are a few ways you can do this. One way you can it is to add a waterfall. Constant running water exposes lots of water molecules to the air. But, depending on the size of your pond, it may not be enough. Keep a close eye on your pond for signs that the waterfall is not sufficient aeration. Another excellent way to ensure plenty of gas exchange is to install an aeration system or air pump. The size of the aerator you need depends on the surface area, depth, and even shape of your pond. If you have a waterfall or fountain you can get away with a smaller system. We recommend consulting with a professional to pick the right system for your pond.

Water Temperature

The temperature of the water has an effect on how much oxygen it can hold. Hot water can hold less oxygen than cold water. This means that you have to pay close attention to your pond during the summer months. Do your fish suddenly start to die as the weather begins to warm? This is because the water needs less aeration during the winter to provide enough oxygen. Simply adjust your aeration system when summer comes to keep your fish alive and happy.

Ready to Aerate?

Is your pond water stinky and dirty all the time? Are your fish dying for no clear reason? Your problem is most likely a lack of oxygen in the water. Contact us today to help you choose the right aeration system for your pond. With the right system, your water will stay fresh and clean, and your fish will thank you for it.
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