No hydroponic system would function properly without aeration. All of the plants would die! Aerating root zones prevents them from drowning and allows the continued uptake of water and nutrients. Meanwhile, plants breathe in oxygen to release energy stores of glucose to fulfill daily functions.

Read on to learn about how to aerate different hydroponic systems, and why it’s so important!

Why Do Plants Need Oxygen?

Simply put, all plant types have oxygen requirements to undergo respiration and root zones need oxygen to avoid drowning.

While plants exhale oxygen while photosynthesizing, they inhale a supply of oxygen while respiring. Plant respiration releases plants’ stored glucose so they can have energy to use for plant growth.

Oxygen at the root zone helps your plants from drowning. Without proper aeration, the roots would become covered with slime and suffocate. Oxygenating the root zone allows the continued uptake of water and nutrients.

The Importance Of Dissolved Oxygen In Hydroponics

Let’s talk about what exactly dissolved oxygen actually is!

Water already has oxygen atoms in it, but they’re chemically bound to the water molecules and therefore that oxygen isn’t available to your plants.

Dissolved oxygen, O2, is the form of oxygen that your plants are able to uptake. This is also the same kind of oxygen that we breathe.

What Affects The Oxygenation Of Nutrient Solution?

Many things impact how much dissolved oxygen is in your water. One of the main factors is the purity of your water. For example, organic contaminants can consume the dissolved oxygen in the water before your plants get to it.

Likewise, salinity, mineral content, and concentration of fertilizer can all affect oxygen content.

To mitigate this, use a reverse osmosis filter before putting your water in your system.

How Do You Aerate Hydroponics Correctly

How to properly aerate your hydroponic system depends on which system you’re using!

For example, DWC benefits from air diffusers or air stones. Ebb and flow systems utilize siphons. NFT and the Krakty method simply rely on an air gap.

Air diffuser

Air diffusers are tubes with holes in them that get hooked up to an air pump. The air is pumped into the tube, and then through the holes, creating air bubbles.

The largest advantage that air diffusers hold compared to air stones is the bubble size. Air diffusers give off smaller bubbles which rise more slowly, hence allowing more contact between the oxygen and the root zones.

That being said, air stones are being developed to create smaller bubbles to bridge this gap!

Air stone

Air stones are porous discs that diffuse air from an air pump into bubbles. The bubbles that come out of air stones are larger than those that come out of air diffusers.

That being said, air stones create a more even distribution of the air. They come in many different shapes, sizes, and materials. Air stones are great for large, extensive root systems.

Air stones are the cheapest way to aerate a hydroponics system.


A siphon sucks water out of hydroponic beds to quickly drain them and provide aeration. Siphons are used in ebb and flow systems.

Siphons come in bell, loop, and U shapes- although they all accomplish the same task.

When water levels rise in the grow beds, the water eventually reaches a standpipe and flows into it. When the standpipe fills up, the siphon sucks all the water out of it, creating a vacuum that drains the whole bed.

Air gap

NFT and Krakty method hydroponic systems both rely on air gaps.

Air gaps are simple. The very bottom tips of the roots touch the nutrient solution, while the rest of the roots are exposed to air. This lets roots uptake water and nutrients while still breathing.


What Is The Purpose Of Aeration In Hydroponics?

Aeration ensures that there is proper oxygenation and that the nutrient solution gets adequately circulated. Aeration keeps nutrients afloat so that your plants can absorb them.

How Much Aeration Is Needed For Hydroponics?

The amount of aeration needed for hydroponics is 1/2 a liter of air per minute per gallon in your reservoir.

Can You Have Too Much Aeration In Hydroponics?

You can have too much aeration in hydroponics. Excess aeration can create a rise in water temperature, prevent the uptake of nutrients, and make your solution overly acidic.

To avoid too much aeration, be sure your air pumps aren’t too strong and that you’re using the right amount of air stones.


Plants can’t survive without aeration. Methods such as air diffusers, air stones, siphons, and air gaps all allow hydroponic systems to function properly and keep plants healthy and happy. To be blunt, you can’t slack on aeration! Your plants won’t make it.

Subscribe to our blog so you never miss a post!