Growing plants hydroponically can be exciting for a beginner since you are growing plants without soil. When researching hydroponics, there are numerous ways to setup a hydroponic system that does not use soil to grow plants.
It can be overwhelming at first when looking at the different hydroponic systems, equipment, and nutrient solutions. So do we need air pumps for hydroponic systems?
Air pumps are necessary for some hydroponic systems where most of the plant’s roots are submerged in water. However, hydroponic systems that leave more of the roots exposed, such as the Kratky Method or aeroponics, do not need an air pump for the plants to grow.
The reason for air pumps in hydroponics is that plants need oxygen in order to survive and grow. The green parts of the plants can get oxygen from the air as the plant produces more oxygen through photosynthesis. However, the plant’s roots need to get oxygen through the soil or water. This is where air pumps can help provide oxygen in the water otherwise the plant will drown.
Let’s go over the hydroponic systems that need an air pump to oxygenate the water. The other hydroponic systems all rely on the plant’s roots absorbing oxygen from the air so they don’t require air pumps.
Hydroponic Systems That Need Air Pumps
Any hydroponic system that has the plant’s roots completely submerged beneath the water will require an air pump. The water needs to be oxygenated so that the roots can absorb oxygen and not drown.
Deep Water Culture (DWC)
DWC is the most common hydroponic system that requires an air stone. The plants usually grow on a floating styrofoam raft or in a container where the water is filled to the roots. In these systems the roots will drown if the water is not oxygenated.
Below you can see a styrofoam raft DWC system.
If there are other hydroponic systems that have the roots completely submerged in the water than an air pump is required.
Aquaponics
Aquaponics is a special type of hydroponics since you are not only growing plants but also fish. As you can imagine, you must have air pumps to help the fish survive and the plants certainly won’t mind having oxygenated water as well.
As you can see above, the water is being oxygenated by an air pump for the fish to survive. The water then gets pumped into the growing tray above where it floods or waters the plants and gets drained back into the water reservoir.
Aquaponic systems can be less complex where the plant growing tray is built on top of an aquarium. This means the plant’s roots will grow into the water where the fish are. Once again, in this example the water is being aerated by an air pump or through the falling water so that the plant’s roots don’t drown.
Hydroponic Systems That Do Not Need Air Pumps
Below are the other common hydroponic systems for growing plants that do not require an air pump. All of these methods either rely on the roots being partially exposed to the air or cycling how often the roots get submerged in water.
Some hydroponic systems still require water pumps while others do not. So we will breakup the remaining hydroponic systems in those that require electricity or pumps and those that do not.
Keep in mind, if you grow indoors then you will likely need grow lights so you will need to use electricity. However, if you grow your plants outdoors or in windowsills then you can avoid using any electricity with some of the following hydroponic systems.
Hydroponic Systems That Use Water Pumps But Not Air Pumps
Aeroponics
Aeroponics is where the plants roots are suspended in the air but there are misters or sprayers that frequently spray the roots to keep them moist. This method is often seen as the most complex as this is what NASA uses to grow plants in space.
Water pumps are needed to pump the water from the water reservoir at the bottom into the sprayers or misters throughout the tower. Aeroponics can also be more horizontal but the concept is the same. Water pumps need to pump water into the sprayers and nozzles so that the plant’s roots can get misted or watered for a period of time.
The plant’s roots typically get sprayed every few minutes in an aeroponic system to keep the roots moist. Otherwise if the roots dry out, these plants will get damaged or die.
Ebb and Flow
Ebb and Flow, also known as Flood and Drain, is where the plants sit in a large tray full of growing medium. The tray is periodically flooded so the plants can be “watered” and then the tray is drained so the plants can get the oxygen they need from the air.
This system requires a water pump to push water from the water reservoir into the growing tray above. Typically the water pump will flood the tray and the water will slowly drain back into the water reservoir below. The time between the floodings is when the roots can absorb oxygen.
Nutrient Film Technique (NFT)
Nutrient Film Technique or NFT systems use water pumped through water channels in order to grow the plants. Commercial setups such as the one seen below use rows of these water channels to grow a lot of leafy greens at the same time.
Similar to the Aeropnics and Ebb and Flow, the water pump in NFT has to pump the water from the water reservoir into the various water channels.
Hydroponic Systems That Do Not Use Electricity
The following hydroponic systems do not need a water pump or air pump. This means these hydroponic systems do not need electricity unless your setup has a grow light.
These two systems are great for beginners since the cost is lower to get started. Not to mention these systems are relatively hands off which means you just need to set these up properly for your plants to thrive.
Kratky Method
The Kratky method, also known as the set it and forget it method, is similar to DWC where the plant sits on top of a water reservoir. Unlike the DWC, you cannot have your plants sitting on a styrofoam raft in the Kratky method.
Instead the plants must sit on top of a lid, such as a bucket lid, so that the roots get exposed to air as the water level declines. This is how the plants get their oxygen as they grow to maturity.
As seen in the image above, this Kratky system in mason jars does not use any electricity to grow these leafy greens. In fact, these plants may grow to harvest without ever having any maintenance done as long as the water reservoir is large enough.
Wick System
The wick system is where the plants sit in a growing tray above the water reservoir and get the water they need through a wick. A wick that sits in the water reservoir will pull up water from the reservoir to the plant’s roots due to capillary action. This is how the plants get the water they need to survive.
The wicks act as a water pump in this setup as the plant draws up water from the reservoir through capillary action. However the wick system can be grown without any electricity, which makes this a beginner friendly hydroponic setup.
Conclusion
Air pumps are not necessary to get started with hydroponics. There are hydroponic systems that do not use air pumps or even water pumps. Hydroponics can be as complex or as simple as you want it to be.
Find a hydroponic system that is within your budget and get started growing today!
