Home / Gardening Guides / All Hydroponic Systems Types Described & How They Work

All Hydroponic Systems Types Described & How They Work

The beginning of civilization was rooted in the agricultural system. The advancement to have cattle and crops around the year helped a civilization flourish.

Humans no longer needed to track down animals and search for plants for food. With the agricultural techniques, we were able to spend time on activities other than searching for food.

However, with time, older cultivation techniques had to be overthrown. The need for humanity to have more food urged us to use newer methods. In the modern world, we face issues of water and land shortage to grow crops. Nevertheless, hydroponics has the solutions we need!

The word hydroponics is a combination of Greek words “hudor” and “ponos,” meaning “water” and “work,” respectively. The loose translation of the word hydroponics is to employ water to work.

In hydroponics, we can employ water to grow crops like never before. Hydroponics involves modern devices and agricultural knowledge for growing crops in greenhouse farms.

With hydroponics, we no longer need soil and fertile land to grow crops. Gone are the days when we had to plow fields and spill gallons of water to irrigate the crops. With the help of hydroponics, everything is now within our reach!

Background of the hydroponics

One of the earliest occurrences of growing plants without requiring soil relates to legendary Francis Bacon. His book on growing plants with a revolutionary technique was published after his death. Next up was John Woodward, with his experiments of growing spearmint. His research concluded that less distilled water was better for plant growth.

It was only known later that there are several elements necessary for plant growth besides clean water and soil. It was realized that crops require more research for more food.

However, after some developments, W. A. Setchell proposed the term Hydroponics to William Frederick Gericke. William wrote a book named “Complete Guide to Soilless Gardening.”

Fast forward to the present year, the industry of hydroponics is expected to grow more than ever in the upcoming decade.

Types of Hydroponic systems

Like any other technique people have employed throughout history, hydroponics also has several ways to grow plants without requiring soil.

Hydroponics is a broad-spectrum field, and so are the ways to grow plants hydroponically. The six major types of hydroponic systems are:

  1. Static solution culture
  2. Continuous-flow solution culture
  3. Passive sub-irrigation
  4. Ebb and flow (flood and drain) sub-irrigation
  5. Run-to-waste
  6. Deep-water culture

Each technique has its benefits and its downsides. However, all of the techniques present modern solutions to the problem of water supply to crops.

With the repetitive farming and the excessive use of herbicides, the fertile land is losing its fertility. We have to find techniques that require less land and nearly no water supply at all.

The techniques of hydroponics allow everyone to neglect the classical needs of farming. Each technique is explained in detail separately.

1. Static Solution Culture

Static Solution Culture Hydroponic System

As the name implies, this hydroponics technique requires a solution of nutrients to plant growth. However, with static solution culture, you do not need to depend on the old farming method.

You do not have to go to your farm to work all day in the hope of getting your crops at the end of the season. Even if you spend months toiling all day long to feed your family and sell food for money, the chances are that diseases attack your crop. Using a static solution, culture removes all such worries from your life.

Working on the static solution culture

In this outstanding method of farming, we have to use pots to store plants. The containers or pots of the nutrient solution are Mason jars and buckets. You can also use tubs or tanks for this purpose. You can choose to aerate or un-aerate the solution. If you choose to keep your solution un-aerated, you have to take care of roots.

The roots of the plants in case of un-aerated solutions should be kept low. By keeping roots low, you can make sure that plants get enough oxygen by air on the surface.

You have to cut or make a hole in the reservoir for every plant in the static solution culture. You only have to make a hole if you have a jar or o pot. You have to put a lid or cardboard/metal on top.

You can allot a single reservoir for a single or many plants in the culture. The size of the reservoir is flexible according to the needs of the plant. If you want to make a homemade system to use the solution culture technique, you can do it easily. All you have to do is to find some food pots to do so.

You can provide proper aeration to your plants in the system with an aquarium pump. The aquarium tubing and valves help the circulation of air throughout the system. One problem arises when you use this culture to grow plants at home or for industrial purposes.

The algae start developing in the water if the water gets enough light. In the case of algae, plants cannot get enough oxygen or nutrients for their survival. You have to keep your pots covered from light to stop the production of algae.

However, the solution culture does not mean that you do not have to take care of the plants like in the classical system. The plants depend upon the nutrient solution provided by you, and you have to change the solution on a planned basis to provide the necessary nutrients to the plants.

An electrical device takes care of the solution for you so you can stay informed about the nutrient level. In the case of nutrient depletion, you can use a Mariotte bottle. The bottle allows you to maintain the level of the solution. However, the raft solution culture makes sure that the nutrient level never decreases.

2. Continuous-flow solution culture

Continuous-flow solution culture Hydroponic System

Another wonder of hydroponics is the continuous-flow solution culture. In this system, the nutrients are supplied constantly to the plants present in the culture.

Taking control of this system is so easy to maintain that this system is used around the world due to this feature. It is not a difficult at all to check the temperature of the culture in this method. You can take care of thousands of plants at the same time with this technique.

NFT, the variation

Nutrient film technique, NFT, adopts a very low stream of water containing necessary elements for plant growth. This method also enables plants to get the oxygen necessary for well-being. An NFT system uses the right channel slope and the exact rate of flow in the right channel length. This helps maintain a healthy environment for the plants in the culture.

In this variation of continuous-flow solution culture, plants get adequate water, oxygen, and nutrients at the same time. All other techniques of hydroponics lack an adequate supply of water, nutrients, and oxygen, but NFT keeps all the factors in balance.

The simple setup of NFT is utilized everywhere when people choose hydroponics because of its ability to keep plant life protected. The adequate supply to the lifeline things for plants results in a production that is more than any other technique. However, the system is not resistive to the changes inflow.

The only way to maintain the system is to provide the flow continuously.

3. Passive sub-irrigation

Passive sub-irrigation Hydroponic System

This technique is one of the best methods in hydroponics to make sure that you can grow plants indoor plants without requiring fertile land at all. With a canning jar, clay pellets, a hydroponic fertilizer, seeds, and a light, you can grow plants without taking care of daily plant chores at all.

You can grow basil in your living room without having to do almost anything after you set up the system. Passive irrigation lets you actively participate in your daily activities, and the passive system takes care of growing plants.

Working method

Passive sub-irrigation allows you to grow plants without soil or bark. A porous medium uses the capillary action method to pass water and necessary nutrients direct to the plant roots. The supply of water and the necessary ingredients are already present in the system. You do not have to take care of supplying nutrients regularly.

This is the simplest method to grow plants in your home. A shallow pot is dipped in the solution of fertilizer and water that has the perfect combination of nutrients. As the task of taking care is not hectic at all, you can also employ this technique to grow plants in large amounts.

However, supplying an adequate amount of oxygen may become a real problem in this system. To tackle the possible lack of oxygen, systems are so arranged that they get a supply of oxygen regularly. Plants are naturally adopted to have long roots. However, this method refrains plants to grow long roots to gain the necessary nutrients.

This technique already meets the necessities of a plant, so the plant can focus on developing shoots instead of roots. Employ this method to have a clean and green home without worrying about taking care.

4. Ebb and Flow

Ebb and Flow Hydroponic System

Simplicity, reliability and low-cost points make this system one of the most sought-after in the world of hydroponics. In this method, the pots have an inert medium. The purpose of the inert medium is not to provide necessary nutrients or act like soil.

However, the inert medium doesn’t function as the temporary source of water and nutrients to the plants growing in the culture. A hydroponic system takes care of the rest of the nutrition and watering.

A watertight growing bed holds the pots in the medium for the culture. Lava rock, Rockwool cubes, or fiber constitutes the inert medium in this system.

The product of making a mixture of these items makes something that can store water and nutrients. A supply tank of nutrients provides necessary nutrients to this mixture on fixed times. You can place the supply system below the inert medium to fill the inert system with nutrients automatically.

With this method, you can even grow bigger plants if you will do so. However, you have to take care of pH and other water factors, for it is a closed system. Keeping care of the level of nutrients and proper oxidation is also necessary for plant survival.

Aeration in this system

In any hydroponic system, aeration is the basic factor. Like all the systems, aeration takes the central ground in here. However, the ebb and flow system have the answer to aeration problems.

The Automatic displacement takes the deoxygenated air from the water flow automatically. Upon turning off the pump, the water settles down. Upon settling of water, roots get oxygen from the surroundings.

During ebb, the water enables the roots to absorb oxygen and facilitate re-oxygenation that roots can sustain in case they stay wet. The root area stays free from the fear of any fungus or bacterial activity because of the high oxygen content of the system.

This system is also resistive to phythim, while other hydroponic systems cannot defend against this root-rotting mold. No need for supplementary oxygenation by air pumps means that you can rely on the sustainability of the system.

This system only takes a minimum amount of electricity to operate. You cannot overlook this system if you have low resources for electricity. One of the primary benefits of the system is that it does not produce noise.

5. Run-to-waste, aka The Bengal System

RUN TO WASTE Hydroponic System

Run to waste (RTW) or the Bengal system means that the water is supplied to the plant, moves around the plant and irrigates it. Then, it ends up in a collection point for other uses. The water in this system is not filled with nutrients. The system does not store the nutrients for other cycles.

You can set this run-to-waste system in many styles. The simplest method is to apply nutrients daily to the growth media. You can even get this system automated by using delivery pumps and tubing for irrigation of a frequency adjusted by the timer.

All of the plant factors like its size and growth when and how much the automated setup irrigates the system. The computer or PLCs handle all of the working or industrial applications of the system.

Run-to-waste hydroponics is applied to produce potatoes, tomatoes, and other plants on a commercial basis. If you want to be environment-friendly, you can store the waste of the system within the plant to clean and reuse it. You can even grow bonsai with the run-to-waste method.

6. Deep-water culture

Deep Water Culture Hydroponic System

The method of producing plants by hanging roots water containing nutrients and oxygen is the deep-water culture. In some places, this method is also known as raft or float system. Water almost 1-foot deep houses floating rafts. The floating rafts carry the plant roots to the water supply.

In this method, there are no compartments to hold the waste. In this way, the built infiltration techniques are used to filter the plant for use. Because the filtration system requires the most advanced techniques, the setup cost of this method rises exponentially.

Older techniques

A five-gallon bucket with an air stone housing an air pump with a net pot was the basic system for this technique in the past. The availability of the buckets and the lower prices urged early users of this system to adopt 5-gallon ones. Net pots are in different sizes, from six to ten inches.

A hydroponic medium like Hydroton is placed in the pots for holding the plant’s base. Airstone does the job of oxygenation. Airstone is connected to the air pump with an airline. The plant keeps growing under ideal conditions to have a higher root mass. The plant’s growth alters the pH and other factors, and the supervision of the system is required.

Development of the Recirculation Deep Water Culture

An old technique wants you to look for each bucket and to measure its pH and conductivity factor on one by one basis. However, the Recirculation Deep Water Culture (RDWC) systems bins using a PVC pipe are connected. For pulling water, a pump is present in the system.

This system allows the clearing and aeration of each system more carefully and easily. You can control the pH and CF of the entire system due to its interlinked connectivity. The only issues with this system are about cleaning and taking care of its temperature.

Supporting items for hydroponics

No system can run without the necessary components. In hydroponics and its techniques, you have to depend upon the supplies necessary for the processes. Here are the items necessary to carry the types mentioned above.

Expanded clay aggregate

To carry out the hydroponics methods, we need to use baked clay pellets that are capable of supporting nutrients and supplying water. The inert and pH-neutral nature of the clay pellets makes them ideal for hydroponics.

Not any nutrient value is added in the pellets, but they are super useful to hold the nutrients supplied by the hydroponic fertilizers. The pellets are round, and they are baked in a kiln.

The high temperature of the kiln makes the pellets porous to circulate water and nutrients. The pellets are not heavier at all and stay the same upon usage. The shapes of pallets might be the same or different. The process of making pellets decides its shape.

Expanded clay is used to make clay pellets for several uses. Some people argue against reusing the pallets as they contain roots from the previous crop.


The glass waste is used to make useful grow stones for hydroponics. These are used for their ideal water and air retention. These are more useful for use in hydroponics.

Coir peat

Coco peat contains the material left after clearing fiber from the coconut shell. Coir is a universal material for flowering and growth. Coconut-coir, along with Trichoderma fungi, keep roots safe. When the root safety is made sure with the coir, the growth of roots speeds up.

You cannot overwater any plant having coir, as its base for coir can keep water in balance naturally. Coir can store nutrients for the plants, making the plants able to use the nutrients at any time. In the form of coco peat, you can get coir for your plants. Although the coir physically resembles clay, it has no nutrient contents at all.


Gravel is used in aquariums, and you can use it in hydroponics by prior washing it. A gravel filter bed keeps water circulated with the electric pumps.

This material is not expensive at all for use in hydroponics. It will not become heavy with water. You have to keep the circulation system working properly to save it from waterlogging.

Sheep wool

Sheep wool is a growing material that is commonly overlooked by those who use hydroponic techniques. Sheep wool can allow cucumber plants to grow faster compared to any other bedding material.

It allows greater air and water flow compared with peat or coconut fiber slabs. The sheep wool proved in a study that allows the plants to grow faster.

Final words

In the modern world, we have downtrodden people that do not have the power to fill their tummies. Food wars are going to tear apart the fabric of society. In the world full of chaos and instability, providing a stable stream of food is the need of the hour.

With the increased price of production of food, it is high time to look for alternatives.

We do not have to look anymore for alternatives as we all have the hydroponic techniques to supply food to our next generations.

It is the duty of humans around the globe to invest in hydroponics for a stable life! Use hydroponics now to save your life and the life of others with ease!