The (DWC) – Deep water culture is among the significant techniques that deal with hydroponics.
It is the purest form of hydroponics, with a more straightforward concept as compared to other methods.
As the easiest and effective system, it can be built using different materials that are cost-effective.
What is a deep-water culture system?
DWC is a hydroponic technique that contains plants grown in a nutrient-rich solution that has oxygenated water.
In this technique, the plants are watered continuously as compared to the other hydroponic systems like Ebb and Flow, Aeroponics, and Drip system.
The technique requires a container, a pump, a lid, and a net pot.
The purposes of these requirements in the system are the container or reservoir is used to hold enough water and nutrient solution, having more water in the container provides stability in the nutrient solution, hence requiring less monitoring and maintenance.
The lid is used to offer support to plants growing in the net pot; then, the roots get suspended into the nutrient solution which is in the container.
How do deep water cultures work?
Deep water culture systems always require oxygen, water, and a suitable environment for the plants to survive and thrive well.
The DWC solves the oxygen using an air pump when it comes to action.
The system uses falling water or air pumps to provide air bubbles rising from the dissolved water and nutrient solution in the reservoir.
Plants in deep water culture systems tend to absorb enough dissolved oxygen from the water and sufficient nutrients; this assists them to grow better and at a faster rate than plants grown in the soil media.
The roots of the plants must be suspended in water all the time, with this, the growers need to know that the air pump and the airstone run all the time smoothly.
Lack of the two apparatus insulates that the roots are likely to suffer from being drenched and might finish the amount of oxygen available.
The system contains a reservoir that stores water and nutrients; the air stone is linked with the air pump through the airline to the water and nutrient reservoir.
The plants’ roots are suspended from the net pots into the water and nutrient solution in the airlines.
The technique’s net pots are made of recyclable and firm plastic mesh.
The mesh system permits the plants to have a healthy and robust root network system.
For growers with regular cups with holes at the bottom, they only let the plants grow in one direction.
But with standard net pots, the roots can extend to any direction of their choice; this is very important because it encourages a dynamic root network system.
And once the plants’ roots touch the nutrient and water solution, a growth blast occurs.
You will notice that when you grow plants in the deep-water culture system, the plants’ roots absorb water and nutrients immediately.
And if the water is correctly oxygenated, the roots would remain immersed in the water for the growth cycle to take place.
This ensures that the roots are not suffocated.
This is made possible by the sufficient air and oxygen they receive from the air bubbles intensifying through the dissolved oxygen and nutrient solution.
In this system, when more air bubbles are produced, the more the air supplied.
For instance, when air bubbles rise from the bottom to the top of the water, the plants are more likely to survive and thrive.
What are the components of a Deep Water Culture?
The deep-water culture technique comprises of;
- Water reservoir
- Net pots
- Air pump
- Airstone
- Hydroponic nutrients and pH adjuster
– Water reservoir
In this hydroponic technique, the roots get suspended into the net pots from above. The plants’ rooting network reaches down to be fully dipped in the nutrient solution.
For some systems, each plant has its reservoir while others one reservoir is shared among several plants.
For plants that share the reservoir, it might be quite challenging to grow a variety of plants.
Individual reservoirs provide more suppleness and control over the plants that grow there.
Most reservoirs are made of dark containers. They have lids, where holes are made with ample space to support the net pots.
The net pots are then filled with planting media. In the reservoir, no light is allowed; this ensures that the growth of algae or bacteria is prevented.
Since the plants’ roots are exposed, they might fall obscene of air thinning if the light is there for a prolonged time.
Growers are also advised to use lids with reflective materials to prevent ambient light from heating the reservoir, thus preventing light from being reflected on the underneath of the plants.
-Net pots
Net pots are small containers that are made of mesh bottom. The mesh bottom is where the plants’ roots are suspended from to reach the nutrient solution below them.
The net pots also act as the placeholders for the planting medium with low water retention properties.
For this kind, clay pebbles are suitable because they permit maximum airflow to touch the roots.
Before growing is done in the net pots, the seeds need to be germinated first then transferred into pots once they are big enough.
Experts advise growers when transferring the seedlings into the net pots; they should ensure that the roots are fully immersed in the nutrient solution.
The main difference between net pots and regular cups is that the net pots have no solid part.
-Air pump
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In the deep-water culture technique, an air pump is a necessity. The air pump ensures the nutrient solution and water are continuously pumped from the reservoir throughout the entire system.
The air pump also provides that there is even distribution of water and nutrients in the system.
When installing an air pump in the deep-water culture system, the tubes used should always be black; this prevents the growth of algae in the system.
Regular checkups should be done to the tubes, containers, and lids to avoid such extensions.
Growers are advised by the experts to select air pumps with more than two outlets; this would permit the placement of the air stones in different positions of the water and nutrient reservoir to provide adequate oxygen.
It is important to note that the air pump needs to run all the time for this technique.
-Airline
Airline tubes are also essential products in the DWC system.
The tubes depend on the design, and their function is to deliver the solution from the nutrient solution reservoir to the net pots across the system.
The right size ensures even distribution of the nutrient and water solution.
Hydroponic nutrients plus pH adjusters
In a deep-water culture system, pH levels are very crucial.
They should range from 5.5 to 6.5, with the optimum level being 5.8.
The levels assist the growers in understanding when to use less nutrients and when to add nutrients into the system.
With the pH adjusters in the system, they ensure that the monitoring of the nutrients run smoothly and cautiously.
Deep Water Culture Aeration
In a deep-water culture system, plants require oxygen for their growth and development.
Even though they would receive some air from the clay pebbles, it might not be sufficient to sustain the plants.
Air pumps and falling water then come in handy when providing aeration in the system.
Types of Deep Water Culture systems
In addition to the outdated DWC system, as described above, there are other modern systems.
The modern DWC systems are of three main types;
- Kratky system
The Kratky DWC system is viewed as a conventional technique during the construction period except that it does not use the air pump. The complete technique is inactive, with no extra features or apparatus added.
This type of system works in such a way it leaves a space between the surface of the nutrients and the plants’ roots.
The Kratky system exposes half of the roots while the other half is completely immersed in the nutrient.
For this system, as the level of water drops, the plants’ roots grow deeper and longer as they follow the water.
- Recirculating water culture technique
The recirculating water culture technique is used when there are scaling challenges. Even a deep-water culture system does not guarantee effective scaling.
This system work across the flood and drain and the deep-water culture techniques. For both, the system does not drain away from the planting area.
In the RDWC system, numerous containers are linked to one main nutrient reservoir; this ensures scaling is done because it only requires extra containers to be included.
Then the dissolved water is passed from the water and nutrient reservoir to every single plant before going back to the reservoir.
Each container has enough plant space for about two to three seedlings depending on the type.
- Bubbleponics system
This is a system similar to the regular deep-water culture, with an extra water pump.
In this technique, the water pump is placed in the nutrient and water reservoir and ensures the nutrient solution to the top of the net pots where the roots of the plants are planted.
The system allows the water to run through the planting medium and flows back to the reservoir after flow through the entire system.
The bubbleponics system is suitable when the seedlings are tiny, and their roots are not long enough to reach the water reservoir.
Once the plants’ roots longer to a point they can touch the reservoir water, then the system is of no importance over the convectional deep-water culture system because their growth is likely to outburst.
The system works because when the plant medium is soil, the plants require to search for smaller water pockets, and in the DWC technique, the water, nutrient solution, and air bubbles are beneath the plants.
- This is a four plant deep water culture hydroponic garden
- Easy to assemble/disassemble, no tools required
- Great for flowers, herbs, vegetables and indoor/outdoor plants
What are the aeration techniques in the DWC?
Aeration in deep water culture is done mainly in two ways;
- Air bubbles
In the DWC system, airstone and air pump are used to supply the needed air bubbles to the nutrient solution.
An airstone is a container with a material that resembles rocks, with small holes that provide tiny bubbles that rise above the surface of the water.
Next, an air pump is joined to the air stone to offer the air volume.
Aeration provided depends on the size of the air bubbles, where the small bubbles provide excellent ventilation for the solution, while large bubbles provide poor aeration.
Well, aeration happens when the air bubbles get to have more contact with the surface of the water.
The contact between the air bubbles and the water substitutes the dissolved oxygen that the roots absorb.
- Falling water
The falling water is the second aeration method in the DWC. Falling water is achieved through surface agitation formed as a result of the falling water splashing.
For the falling water method, the amount of falling water plays a vital role.
The higher the volume of water you have in the system, the more the falling force you will achieve, and with more potent force, the deeper the agitation with more dissolved oxygen there is and vice versa.
This method is more prevalent in commercial DWC because of the amount of water used.
Materials needed to build a DWC
- Container with a well-fitted lid (Deep Water Culture bucket)
- A garbage bag with an opaque material
- Net pots
- Drill
- Air pump and air stone with a fitted tubing
- Planting medium
- Nutrients
- Water
Steps to building a DWC
- Drill holes for net pots
The first step when building a deep-water culture is to ensure the net pots have holes at the bottom. For growers using the regular, they should form holes for their cups.
When using the net pots, there is a guiding size; growers are allowed to drill a hole through the center of the lid.
The hole should be big enough to fit a net pot perfectly. Growers are permitted to drill as many holes as possible that can fit the size of a tote lid.
For some totes, it might take up to a minimum of 12 holes after spacing the plants about 3 to 4 inches apart from each other.
After all the drilling, the scraps should be rinsed out. Then the net pots are then placed on top of the tote lid.
You should also ensure the holes are large enough to fit plants’ roots completely and leave space for expansion.
- Set up the air system
The second major step is to set up the air system. Growers should ensure they assemble the air system that offers sufficient oxygen to the roots.
The air hose should have enough space and length to fit in the middle of the reservoir where the air pump would be placed.
Then it will be linked to the airstone and connected to the lid; this will allow efficient airflow.
- Mixing up the nutrient solution
The third step after the air system is to ensure the plants are ready for planting, then mix the nutrients by adding the right additives and balancing the pH levels in the reservoir.
Later top up with enough water to ensure the roots are covered. The mixture should be noted down to keep check during the recheck or when putting fresh nutrient solution.
Nutrient solution mixture is a simple process for making a nutrient solution. The process is to use a small-sized container and fill it nearly to the top then top with water.
Later add the dry nutrients and add the nutrient solution to the reservoir where the plants are suspended. Growers should ensure the measure of the nutrient solution’s electrical conductivity.
The EC should range from 900 ppm to about 1300 ppm for the growth of different types of lettuce and herbs.
After every harvest is done, always check the electrical conductivity, and add water and nutrients when needed to maintain the EC range.
- Adding plants
The final step, when setting up a DWC system, is to grow the plants into the system.
Growers are permitted to start with bare-foot seedlings or plants in the planting medium, for example, the use of rock wool. Then a little of clay pebbles are added into the net pots to set the plants.
Some of the best plants to grow in a DWC system include tomatoes, lettuce, basil, bell pepper and other leafy plants
What is the lighting for the DWC system?
When plants are grown in open field conditions setting, they tend to receive adequate light directly from the sun during the day and rest during the night.
But if the plants are grown indoors, they lack enough light in deep water culture systems; for example, the large systems such as the recirculating deep-water culture artificial lights are used to produce light to the seedlings.
According to experts, growers should find types of light that do not radiate heat because the system emits enough heat from the air pumps running continuously.
The type of artificial lighting to invest in for the growing setup mainly depends on the size of the growing area, the type of plants grown in the system, type of lights, and the growth phase.
The supplementing lighting should run for about 16 hours a day, and the other 8 hours the plants should be allowed to rest in a completely dark place.
Conclusion:
Now that you are equipped with the right information it’s time you build your own hydroponic garden.
Apart from being simple to setup, with hydroponics it is easy to control pests and diseases that attack plants.
Last update on 2025-04-23 / Affiliate links / Images from Amazon Product Advertising API