Hydroponics is a soilless growing method where plants receive a water-based nutrient solution,[1] giving growers precise control over the growing environment and inputs like water, nutrients and oxygen. Several hydroponic systems—varying in size, complexity and efficiency—are available. These setups can be:
- Open or closed:
- Open systems discharge the nutrient solution after use.
- Closed systems recirculate the nutrient solution for reuse.
- Active or passive:
- Active systems use pumps to deliver the nutrient solution to plants.
- Passive (e.g., wick) systems give roots immediate access to the nutrient solution or rely on capillary action to transport it.
Hydroponics is a soilless growing method where plants receive a water-based nutrient solution,[1] giving growers precise control over the growing environment and inputs like water, nutrients and oxygen. Several hydroponic systems—varying in size, complexity and efficiency—are available. These setups can be:
- Open or closed:
- Open systems discharge the nutrient solution after use.
- Closed systems recirculate the nutrient solution for reuse.
- Active or passive:
- Active systems use pumps to deliver the nutrient solution to plants.
- Passive (e.g., wick) systems give roots immediate access to the nutrient solution or rely on capillary action to transport it.
In this blog post, we’ll explore six of the most widely used hydroponic systems, explaining their pros and cons to help you choose the best setup for your grow operation.
Figure 1. Types of hydroponic systems. Image source: Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Potato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
Nutrient film technique (NFT)
NFT gets its name from the thin, flowing stream, or film, of nutrient solution that feeds the roots. In an NFT system, plants grow in net pots placed in shallow channels, with the bottom half of the roots exposed to the nutrient film and the top half exposed to the air.[2] This ensures a continuous supply of water and nutrients, as well as ample oxygenation because the roots are not fully submerged.
Popular for its efficiency, NFT uses minimal water and nutrients and is a closed-loop system, so the nutrient solution is recycled. The channels are sloped, allowing the nutrient solution to flow naturally over the roots before returning to the reservoir for reuse. The only energy required is for pumping the nutrient solution to the top of the channels, whether continuously or timed.
Nutrient film technique (NFT)
NFT gets its name from the thin, flowing stream, or film, of nutrient solution that feeds the roots. In an NFT system, plants grow in net pots placed in shallow channels, with the bottom half of the roots exposed to the nutrient film and the top half exposed to the air.[2] This ensures a continuous supply of water and nutrients, as well as ample oxygenation because the roots are not fully submerged.
Popular for its efficiency, NFT uses minimal water and nutrients and is a closed-loop system, so the nutrient solution is recycled. The channels are sloped, allowing the nutrient solution to flow naturally over the roots before returning to the reservoir for reuse. The only energy required is for pumping the nutrient solution to the top of the channels, whether continuously or timed.
However, because NFT is a recirculating system, it requires careful monitoring to maintain nutrient balance and system stability.
NFT is also highly scalable, as growers can simply expand the system by adding more channels. However, due to the narrow width of the channels, it is better suited to plants with smaller root systems.
Deep water culture (DWC)
Also called a hydroponic bubbler system, DWC[3] involves growing plants in net pots secured by a container lid or floating platform in a reservoir, often called a grow tank, filled with a nutrient solution. The roots are fully submerged in 6–8 inches of nutrient solution,[4] and air is pumped into the tank to provide oxygen.
A simplified variation of this is the Kratky method (Figure 2). Instead of pumping oxygen into the nutrient solution, at least 50% of the roots remain exposed to the air. To achieve this, net pots are suspended above the nutrient solution, guaranteeing that the roots always have access to oxygen. As the root system grows, the nutrient solution level may need to decrease.[5]
Deep water culture (DWC)
Also called a hydroponic bubbler system, DWC[3] involves growing plants in net pots secured by a container lid or floating platform in a reservoir, often called a grow tank, filled with a nutrient solution. The roots are fully submerged in 6–8 inches of nutrient solution,[4] and air is pumped into the tank to provide oxygen.
A simplified variation of this is the Kratky method (Figure 2). Instead of pumping oxygen into the nutrient solution, at least 50% of the roots remain exposed to the air. To achieve this, net pots are suspended above the nutrient solution, guaranteeing that the roots always have access to oxygen. As the root system grows, the nutrient solution level may need to decrease.[5]
DWC is one of the simplest, most affordable hydroponic systems, but due to the large volume of water and nutrients involved, it is less efficient than other methods. While DWC is a passive system, it still requires regular maintenance and monitoring:
- Water temperature, pH, salinity and dissolved oxygen must be carefully adjusted to ensure ideal growing conditions and prevent biofilm and root disease.[6]
- The nutrient solution level must be maintained:
- If it’s too low, the roots won’t absorb enough nutrients.
- If it’s too high, growers risk submerging the stem and drowning the plants.[7]
Figure 2. The Kratky method and how the nutrient solution level is decreased as the root system develops. Image source: Gumisiriza, Margaret S., Patrick A. Ndakidemi, and Ernest R. Mbega. 2022. “A Simplified Non-Greenhouse Hydroponic System for Small-Scale Soilless Urban Vegetable Farming.” MethodsX 9: 101882. https://doi.org/10.1016/j.mex.2022.101882.
Figure 2. The Kratky method and how the nutrient solution level is decreased as the root system develops. Image source: Gumisiriza, Margaret S., Patrick A. Ndakidemi, and Ernest R. Mbega. 2022. “A Simplified Non-Greenhouse Hydroponic System for Small-Scale Soilless Urban Vegetable Farming.” MethodsX 9: 101882. https://doi.org/10.1016/j.mex.2022.101882.
DWC is one of the simplest, most affordable hydroponic systems, but due to the large volume of water and nutrients involved, it is less efficient than other methods. While DWC is a passive system, it still requires regular maintenance and monitoring:
- Water temperature, pH, salinity and dissolved oxygen must be carefully adjusted to ensure ideal growing conditions and prevent biofilm and root disease.[6]
- The nutrient solution level must be maintained:
- If it’s too low, the roots won’t absorb enough nutrients.
- If it’s too high, growers risk submerging the stem and drowning the plants.[7]
DWC is one of the simplest, most affordable hydroponic systems, but due to the large volume of water and nutrients involved, it is less efficient than other methods. While DWC is a passive system, it still requires regular maintenance and monitoring:
- Water temperature, pH, salinity and dissolved oxygen must be carefully adjusted to ensure ideal growing conditions and prevent biofilm and root disease.[6]
- The nutrient solution level must be maintained:
- If it’s too low, the roots won’t absorb enough nutrients.
- If it’s too high, growers risk submerging the stem and drowning the plants.[7]
Figure 2. The Kratky method and how the nutrient solution level is decreased as the root system develops. Image source: Gumisiriza, Margaret S., Patrick A. Ndakidemi, and Ernest R. Mbega. 2022. “A Simplified Non-Greenhouse Hydroponic System for Small-Scale Soilless Urban Vegetable Farming.” MethodsX 9: 101882. https://doi.org/10.1016/j.mex.2022.101882.
Drip
Similar to NFT, a drip system pumps the nutrient solution directly to the roots at set intervals. However, instead of providing a continuous stream of nutrients, the nutrient solution is dripped onto the roots via hoses and emitters,[8] allowing growers to control the flow rate and customize the amount of nutrients plants receive.
Thanks to this precision, drip systems are ideal for heavily loaded crops and for growers who want strict control over feeding.
Drip
Similar to NFT, a drip system pumps the nutrient solution directly to the roots at set intervals. However, instead of providing a continuous stream of nutrients, the nutrient solution is dripped onto the roots via hoses and emitters,[8] allowing growers to control the flow rate and customize the amount of nutrients plants receive.
Thanks to this precision, drip systems are ideal for heavily loaded crops and for growers who want strict control over feeding.
A drip system is also easily scalable and can be water-efficient if designed as a closed-loop system; excess nutrient solution simply needs a channel to flow back into the reservoir.[9] As with all closed-loop systems, diligent monitoring of the recycled nutrient solution is required to maintain nutrient balance.
However, due to the large number of hoses and emitters, drip systems are more prone to biofilms and clogs, requiring regular cleaning.[10]
Ebb and flow
In ebb-and-flow[11] systems, the nutrient solution is periodically flooded and drained over plants grown in porous beds or containers filled with an inert growing medium (e.g., perlite, coconut coir, rockwool). A timer-controlled pump floods the system until the nutrient solution reaches just below the top layer of the growing medium to prevent overflow. Once the flow stops, the nutrient solution drains back into the reservoir for reuse.
Ebb and flow
In ebb-and-flow[11] systems, the nutrient solution is periodically flooded and drained over plants grown in porous beds or containers filled with an inert growing medium (e.g., perlite, coconut coir, rockwool). A timer-controlled pump floods the system until the nutrient solution reaches just below the top layer of the growing medium to prevent overflow. Once the flow stops, the nutrient solution drains back into the reservoir for reuse.
If the system has proper drainage, this cycle ensures plants receive essential nutrients and ample oxygen. Otherwise, poor drainage can lead to root oversaturation, increasing the risk of root rot. Ebb-and-flow systems are also more prone to algal growth, requiring regular maintenance.[12]
Since ebb and flow is a closed-loop system, it is water- and nutrient-efficient. However, setup and maintenance can be costly, as grow beds must be spacious and packed with the appropriate growing medium.
Wick
Wick systems are passive, relying on capillary action to transport water and nutrients from the reservoir to the roots. A wick made of absorbent fiber such as nylon or cotton connects the growing medium to the reservoir. As the growing medium dries, the wick draws the nutrient solution and delivers it to the plants. Absorbent growing media like perlite or vermiculite are typically used to aid in the wicking process.
Wicking is one of the simplest, low-cost hydroponic systems available, as it does not require pumps, aerators or even electricity,[13] making it ideal for beginners or low-maintenance growers.
However, wicking has a slower nutrient and water delivery rate than other methods, leading to slower plant growth. Uneven absorption of the nutrient solution can also cause salt buildup in the growing medium, so it’s essential to flush the system with fresh water every 1–2 weeks to remove excess nutrients.
It’s also an exclusively open-loop system, as capillary action makes nutrient cycling impossible. Additionally, it is prone to oxygen limitations and algal growth, making it less common for commercial applications.[14]
Aeroponics
As the name implies, aeroponic systems suspend plants in the air using an enclosed tube or vertical tower. The nutrient solution is delivered to the exposed roots as a fine mist or as tiny droplets, either continuously or at timed intervals, through pressurized nozzles. This not only supplies highly oxygenated nutrients,[15] but the heightened oxygen also accelerates growth.[16] However, because the roots are exposed to the air, misting must be properly timed to prevent them from drying out. Additionally, cold temperatures can affect misting,[17] making this system less suitable for grow rooms without climate control.
Excess mist or droplets fall back into the reservoir for recirculation, making aeroponics a highly water-efficient, closed-loop system, using up to 95% less water than other methods.[18] Research shows it is one of the most productive systems; one study found that aeroponics produced the highest number of potato mini-tubers per plant compared to DWC and NFT.[19]
However, aeroponic systems have higher startup costs due to the equipment and technology involved and require more complex management. Additionally, mister nozzles are prone to clogging and need regular cleaning.[20]
Aeroponics
As the name implies, aeroponic systems suspend plants in the air using an enclosed tube or vertical tower. The nutrient solution is delivered to the exposed roots as a fine mist or as tiny droplets, either continuously or at timed intervals, through pressurized nozzles. This not only supplies highly oxygenated nutrients,[15] but the heightened oxygen also accelerates growth.[16] However, because the roots are exposed to the air, misting must be properly timed to prevent them from drying out. Additionally, cold temperatures can affect misting,[17] making this system less suitable for grow rooms without climate control.
Excess mist or droplets fall back into the reservoir for recirculation, making aeroponics a highly water-efficient, closed-loop system, using up to 95% less water than other methods.[18] Research shows it is one of the most productive systems; one study found that aeroponics produced the highest number of potato mini-tubers per plant compared to DWC and NFT.[19]
However, aeroponic systems have higher startup costs due to the equipment and technology involved and require more complex management. Additionally, mister nozzles are prone to clogging and need regular cleaning.[20]
Aeroponics
As the name implies, aeroponic systems suspend plants in the air using an enclosed tube or vertical tower. The nutrient solution is delivered to the exposed roots as a fine mist or as tiny droplets, either continuously or at timed intervals, through pressurized nozzles. This not only supplies highly oxygenated nutrients,[15] but the heightened oxygen also accelerates growth.[16] However, because the roots are exposed to the air, misting must be properly timed to prevent them from drying out. Additionally, cold temperatures can affect misting,[17] making this system less suitable for grow rooms without climate control.
Excess mist or droplets fall back into the reservoir for recirculation, making aeroponics a highly water-efficient, closed-loop system, using up to 95% less water than other methods.[18] Research shows it is one of the most productive systems; one study found that aeroponics produced the highest number of potato mini-tubers per plant compared to DWC and NFT.[19]
However, aeroponic systems have higher startup costs due to the equipment and technology involved and require more complex management. Additionally, mister nozzles are prone to clogging and need regular cleaning.[20]
Choosing the right system
When selecting a hydroponic system for cannabis cultivation, consider factors such as:
- Operation size (hobbyist versus commercial)
- Startup investment and monitoring and maintenance costs
- System complexity and the grower skill level required for management
- Overall productivity and efficiency.
Our general recommendations:
- For beginners and small-scale growers: Wick and DWC. These simple, low-cost systems are ideal for growing small- to medium-sized cannabis plants.
- For larger-scale, experienced growers: NFT, aeroponics and drip systems. These efficient, precise and scalable setups are better suited for commercial production.
Whether a grower is experimenting with hydroponics for the first time or developing a highly efficient commercial setup, there is a hydroponic system suited to every experience level.
Emerald Harvest Team
[1] USDA National Agricultural Library. n.d. “Hydroponics.” Accessed February 18, 2025. https://www.nal.usda.gov/farms-and-agricultural-production-systems/hydroponics.
[2] Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Pfotato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
[3] Also called deep water cultivation.
[4] Mullins, Chris, Amber Vallotton, Joyce Latimer, Toni Sperry, and Holly Scoggins. 2013. “Hydroponic Production of Edible Crops: Deep Water Culture (DWC) Systems.” Published July 19. Virginia Cooperative Extension. https://www.pubs.ext.vt.edu/content/pubs_ext_vt_edu/en/SPES/spes-464/spes-464.html.
[5] Gumisiriza, Margaret S., Patrick A. Ndakidemi, and Ernest R. Mbega. 2022. “A Simplified Non-Greenhouse Hydroponic System for Small-Scale Soilless Urban Vegetable Farming.” MethodsX 9: 101882. https://doi.org/10.1016/j.mex.2022.101882.
[6] Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Potato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
[7] Nursyahid, A., T. A. Setyawan, K. Sa’diyah, E.D. Wardihani, H. Helmy, and A. Hasan. 2021. “Analysis of Deep Water Culture (DWC) Hydroponic Nutrient Solution Level Control Systems.” IOP Conference Series: Materials Science and Engineering 1108: 012032. https://doi.org/10.1088/1757-899X/1108/1/012032.
[8] Hoidal, Natalie, Amanda Reardon, Leah Worth, and Mary Rogers. 2022. “Small-Scale Hydroponics.” University of Minnesota Extension. Accessed February 18, 2025. https://extension.umn.edu/how/small-scale-hydroponics.
[9] Ibid.
[10] Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Potato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
[11] Also called flood and drain (i.e., flood-and-drain systems).
[12] Ibid.
[13] Ibid.
[14] Ibid.
[15] Ibid.
[16] Low, Kathy. 2019. “Aeroponics.” Under the Solano Sun, April 2. https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=29823.
[17] Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Potato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
[18] Low, Kathy. 2019. “Aeroponics.” Under the Solano Sun, April 2. https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=29823.
[19] Rajendran, Sasireka, Tenzing Domalachenpa, Himanshu Arora, Pai Li, Abhishek Sharma, and Guarav Rajauria. 2024. “Hydroponics: Exploring Innovative Sustainable Technologies and Applications Across Crop Production, With Emphasis on Potato Mini-Tuber Cultivation.” Heliyon 10 (5): e26823. https://doi.org/10.1016/j.heliyon.2024.e26823.
[20] Low, Kathy. 2019. “Aeroponics.” Under the Solano Sun, April 2. https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=29823.
