Last Updated on October 10, 2024 by Alice Benny
Hydroponics is the process of growing plants without soil. There are many different ways to do this and it depends on the needs of the grower. Many people interested in gardening want to know what are the 6 types of hydroponics? As a popular alternative to traditional soil farming, hydroponic methods have an excessive number of benefits.
You can use many different hydroponic systems to grow an assortment of plants, such as fruits and vegetables.
Two popular types of hydroponic systems are deep water culture and ebb and flow. Deep water culture involves submerging plant roots in a nutrient rich solution, while ebb-and-flow involves flooding and draining the pots with nutrient rich solution.
There are many types of hydroponic systems, but they can be broadly categorized into two main categories: passive and active. Passive systems don’t require any outside energy input from a pump or fan, whereas active systems do.
Passive hydroponic systems include the wick system, ebb and flow aka the flood and drain system, and the nutrient film technique. Active hydroponic systems include aeroponics, aquaponics, and deep water culture.
How Many Types of Hydroponics Are There?
There are six types of hydroponics that you can take advantage of. Some are better suited for commercial ventures, while others are quite easy to maintain at home.
1. Deep Water Culture (DWC) Systems
Deep water culture is one of the simplest types of hydroponics to explain since it’s quite straightforward. With this system, your plants’ roots will be fully submerged in a nutrient-rich solution, allowing them to absorb nutrients.
Compared to other methods, like wick systems, deep water culture allows you to oxygenate and feed your plants quite well.
Within the basin where you place the nutrient-rich solution, you will also have aerating tools like aerating stones. This equipment is responsible for producing oxygen bubbles and diffusing air through the water, ensuring the roots are oxygenated.
You might also find that this is one of the purest forms of hydroponics because it has plenty of features similar to a fish tank.
Many places around the world, including Japan, use this system. Most companies will use it to grow lettuce hydroponically and other plants that can be placed on free floats.
Pros of DWC:
- Allows roots to be fully submerged
- Plants easily absorb nutrients
- Relatively easy to construct
- Works well with all plants
- Plants will grow quickly
Cons:
- Likelihood of root disease
- Requires consistent maintenance
2. Nutrient Film Technique (NFT) Systems
When using NFT, you won’t have to worry about relying on a growing medium to keep your plants secure. This process is entirely water-based and requires the use of pre-designed channels to deliver nutrients.
You will need to put the nutrient-rich solution into your reservoir, which will then be pushed into channels. Your plants’ roots will be in the channels that let the solution flow over the roots and back into the reservoir.
Instead of completely submerging the roots as you would in in a deep water culture system, NFT allows water to be recycled easily.
When designing a nutrient film technique hydroponic system, you will need to use smaller plants, especially since the channels are small.
Pros of NFT:
- Easy to scale for small or medium-size plants
- Useful for growing small and large plants simultaneously
- Doesn’t require a growing medium
Cons:
- Mostly useful for plants with small roots
- Not really ideal for massive plants
3. Ebb and Flow (Flood and Drain) Systems
Ebb and flow systems are highly popular for commercial and at-home ventures. Another name for this system is flood and drain. You’ll find most home gardeners will use this system because it’s easy to maintain and design. It’s also easy to DIY.
With an ebb and flow system, you will have plants growing in pots placed in a growing bed (large plastic tray) that contains a growing medium (an aggregate such as Rockwool which anchors and supports the plants and holds moisture). When you have your plants and growing medium in the pots, the pump will flood the growing tray / plant tray with the nutrient-rich solution.
You will need to determine the correct height for flooding to ensure your plants’ roots are getting enough nutrients without drowning. This is why having a plastic growing tray with high sides (about 6 – 7 inches in height) is important.
Once the solution has been in the plant tray for a certain period (usually 5 minutes or less), it then drains back into the reservoir. The nutrient solution recirculates.
What makes an ebb and flow system unique is that it requires precise timing to promote your plants’ healthy growth. The good news is you set it up on a timer. How many gallons flush through and how often will be determined by:
- The size of the grow tray
- How many plants you are growing
- How large the plants are; larger plants require more water and minerals
- The inert growing medium you are using; some substrates retain more moisture than others
A mix of coco coir and perlite is ideal for ebb and flow hydroponic systems.
You will need to make sure the input pump pushes and drains the nutrient-rich solution at the right time. It’s also essential to make sure your plants have enough time to absorb enough of the solution to thrive. Learn more about ebb and flow system for hydroponics.
Pros of ebb and flow (also called flood and drain):
- Easy to maintain, low maintenance
- Suitable for most plant types
- Great for root vegetables
Cons:
- Not ideal for large plants
- Relies primarily on the pump controller
- Requires ample space
4. Wick
Another type of hydroponics, wick systems are by far one of the simplest forms of hydroponics that you’ll find. It’s considered to be a passive, non-recovery type hydroponic system.
As a beginner looking for answers to what are the 6 types of hydroponics, you should consider this method because it teaches you the fundamentals.
Wick systems do not require electricity, pumps, or aerators, making them perfect for hydroponic greenhouse systems kits. In this system, you place your plants directly into a porous growing medium. You will then place nylon wicks around the roots of the plants dipped directly into the nutrient solution.
The wicks are then responsible for pulling the nutrient solution into the growing medium, transferring the specific nutrients to your plants.
In the wick system, you can use vermiculite mix, perlite or sand, and a growing medium.
Pros of wick systems:
- Easy to design
- Inexpensive
- No pump, no moving parts
- Great for kids
- Teaches the fundamentals
- Requires limited equipment
Cons:
- Poor distribution of nutrients
- Not ideal for large plants
- Lacks nutrition for most vegetables
- Hydroponic setups
5. Drip Systems
Fortunately, drip is a hydroponics system that is easy to maintain and customize based on your needs. With this system, you will be using a drip system with full control over how much solution each plant receives.
You can then easily adjust the solution’s flow depending on the plants that you have and how often they should be fed. Drip systems also offer plenty of flexibility in terms of scale since they can be large or small.
You can also opt between circulating and non-circulating formats, with circulating systems operating with a constant drip.
Pros to using drip systems:
- Simple to alter
- Reuses unused nutrients
- Perfect for individual plant needs
- Useful for large to small plants
Cons:
- Constant pH monitoring
- Must maintain nutrient levels
- Likelihood of root diseases
6. Aeroponics Systems
While there are differences between aeroponics vs hydroponics, the final type of hydroponics system is aeroponics. It is the most technologically-advanced of the hydroponic setups. With aeroponics, your plants will be suspended in the air, typically held by exclusive clips.
With specialized misters, a nutrient-rich solution will mist your plants’ roots at regular intervals. Since the plants are suspended in the air, they receive both the food and oxygen they need to grow.
If you want a system that will consume the least amount of water, aeroponics is your best option. However, of all the different hydroponic systems, an aeroponics system is one of the more complicated systems to master, especially as a beginner.
Pros to aeroponics:
- Helps to conserve water
- Perfectly feeds plant roots
- Offers optimal oxygenation
- Provides higher yields
- Takes up less space
Cons:
- Difficult to maintain
- Expensive to set up
- Requires regular maintenance
What Are Some Types of Aggregates Used in Hydroponic Systems?
As earlier mentioned, most of the hydroponics systems require aggregates, also known as growing media or aggregate culture, to support the plants’ roots. This aggregate can be anything from small pebbles, gravel, Rockwool, sand, or vermiculite, to chopped-up Styrofoam. The type of aggregate used in a hydroponic system depends on the type of system it is.
Aggregates are an important part of hydroponics systems. They are used to support the plants and hold the nutrient solution. Aggregates provide good aeration and drainage for the plants.
There are a few different reasons why growers might choose to use one aggregate system over another:
- May be cheaper than other methods
- It can be easier to set up and manage
- Larger or smaller, depending on the hydroponics setup; in flood and drain, small aggregates are best. In a drip system, larger aggregates can be used.
There are plenty of different types of aggregates to consider, depending on your needs and budget. We explain 7 of them below, including their pros and cons.
1. Rockwool
Rockwool is by far one of the most popular growing media to use for an assortment of plants. The material is made from melted rock, and then it’s spun into cubes with a very distinct fibrous texture.
You can also find Rockwool in giant slabs, which can be useful for larger hydroponic systems. Plenty of horticulturists believe it’s the best aggregate because it can hold plenty of water.
It’s also known for its oxygenation allowances, ensuring sufficient air is retained for superior root growth. Fortunately, Rockwool is best for vegetative and generative growth cycles without spiking pH.
When working with this material, you’ll want to make sure you soak it overnight to disperse the bonding agents.
Pros of Rockwool:
- Holds substantial water
- Offers optimal oxygenation
- Slow and steady drainage
- Easy to manipulate crops
Cons:
- Doesn’t decompose
- Difficult to dispose of
2. Perlite or Vermiculite
Another incredibly popular form of aggregate for your hydroponic system is perlite or vermiculite. Interestingly enough, these two materials are also made from stone, similar to Rockwool. Perlite is derived from volcanic rock, while vermiculite is typically mixed in and made from mica.
Together, these two substances are lightweight and have a white coloring that can be added to soil to improve aeration and drainage.
This aggregate solution is best for cuttings and starting seeds because it’s incredibly lightweight. It could also be a useful solution for wick systems because they don’t involve rushing water, like ebb and flow systems.
It’s also essential to note that perlite dust can be dangerous, so you will need to wear a mask while handling it.
Pros of Perlite and Vermiculite:
- Very lightweight
- Easy to manage
- Ideal for beginner-friendly setups
Cons:
- Doesn’t retain water well
- Dries out quickly
- Dust can be dangerous for your health
3. Coco Coir (Coconut Coir)
Also known as coconut coir, coconut fiber is an incredibly popular material for different hydroponic systems. This material could likely overtake both perlite and Rockwool in popularity.
Coco coir gives you the ability to use genuinely organic material and has impeccable performance with hydroponics. This material is derived from the husks of coconuts and typically considered as waste. Instead of manufacturers throwing away the material, horticulturists can use coco coir for their gardens.
There are a few different coconut fiber grades that you’ll find depending on your budget and desired salt content.
There is an ample number of benefits to this material, and it’s highly reliable for holding water and oxygen. Overall, coconut coir holds more oxygen than Rockwool and far more water. Also, it has deficient nutrient levels, which means it won’t affect the solution you use for your plants.
Pros to using coco coir:
- Absorbs plenty of water; retains moisture
- Optional low salt content
- Holds plenty of oxygen, good air capacity
- Organic material
- Doesn’t affect pH
- Can recycle it as a soil amendment
Cons:
- Could be expensive
- High salt coir needs leaching
- Types of aggregates used in hydroponic systems
4. Clay Pellets
In comparison to perlite and Rockwool, clay pellets are an incredibly popular alternative aggregate for farmers. This unique material is seemingly designed correctly for hydroponics because it works quite well with several setups.
You can typically find clay pellets from one to 18 mm. They are designed to expand once they absorb water. Within each pellet, there are a ton of tiny air pockets that allow for superior drainage.
This material is highly recommended for ebb and flow systems or any other system that requires frequent waterings.
Clay pellets are also one of the most expensive growing media to consider, but they can be cleaned and reused.
Pros to using clay pellets:
- Great for ebb and flow systems
- Easy to maintain
- Reusable when disinfected
- Allow for perfect drainage
- Easy to flush
Cons:
- Poor water holding capacity
- Dry out easily
- Absorb salt
- Expensive (but you can sanitize and reuse)
5. Gravel
If you’re designing a garden and are searching for the least expensive items to use, gravel is a fantastic aggregate. It was one of the first types of growing medium that you could find for hydroponic systems in their infancy.
Fortunately, it’s readily available from nearly any garden center, so you won’t have to spend a lot of time sourcing materials.
When using gravel, your plants’ roots will have the perfect amount of air, but it’s not ideal for retaining water. Similar to clay pellets, you should only use this material in systems that get frequent waterings. However, it also has the same advantage as clay since you can reuse the material once it has been sterilized.
Pros to using gravel:
- Inexpensive
- Easy to source
- Heavy-duty
- Reusable
Cons:
- Doesn’t absorb water
- Requires frequent watering
6. Sand
If you look into the history of hydroponics, sand is another original material common in old-world systems. It has a strong foundation at the beginning of hydroponics. However, people use sand less in hydroponics and tend to prefer other aggregates. Sand is one of the least used materials today.
Although it is quite inexpensive and heavy-duty, it is not ideal for growing most types of plants. Also, since sand is known for packing down tightly, it doesn’t allow for enough roots to grow and breathe. It’s also not the best material for water absorption.
If you are interested in using sand for your hydroponics garden, your best option is builders’ sand, which has a coarse texture.
Pros of using sand:
- Inexpensive
- Easy to find
- Historically useful
Cons:
- Poor oxygenation
- Doesn’t hold moisture
7. Peat Moss
If you’ve researched hydroponic setups, you’ve likely heard of peat moss because it’s another useful growing medium. Like coconut coir, this material is entirely natural and has an ample number of benefits to the production of vegetables.
Peat moss is known for its highly absorbent composition, and it feels like a sponge, making it ideal for retaining water. It’s also perfect for aeration, ensuring your plants’ roots get the ideal levels of oxygen.
You might find that peat moss is most useful in large net pots, allowing your plants’ roots to wick up water. Peat moss is also known to dissolve over time easily and can increase the likelihood of root diseases.
It also requires far more maintenance than some of the other materials because it can clog your pumps and drip emitters.
Pros to using peat moss:
- Perfectly absorbs water
- Impressive water retention
- Organic
- Easy to use
Cons:
- Decomposes quickly
- Will clog hydroponic setups
What Type of Hydroponic System Is the Best?
When you consider the different hydroponic methods, there are advantages and disadvantages to each. Choosing the best one is dependent primarily on what you want to achieve.
For example, large-scale commercial ventures are likely to benefit more from an ebb and flow system than a wick system. If you want to design a small garden, though, you might find hydroponic methods such as wick systems are more than enough.
Many of the hydroponic system types are similar. To recap, in a wick system, the plants are placed in a container that is filled with a growing medium. A wick is then used to draw water from a reservoir up to the growing medium. Ebb and Flow systems are similar to wick systems, but instead of soil the plants roots are submerged in a reservoir of water. Nutrient Film Technique is also similar to a wick system.
In a NFT system, the plant roots are placed in an open chamber or film of water that is contained within a substrate such as plastic. Plants use transpiration to draw water and nutrients from the reservoir into the growing medium.
By understanding what are the 6 types of hydroponics systems, you can quickly determine which is best for your situation, budget, space, technical abilities and needs.
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