Hydroponics and aquaponics are two highly renowned, soil-less, and sustainable methods of growing food. But, is one better than the other? What are the differences between the two?
Alternatives to traditional agriculture are presenting possibilities for an incredibly sustainable future of growing plants. Two methods, in particular, are favored for growing without soil: hydroponics and aquaponics. Although the two have their similarities, they also have notable differences. But, is one more sustainable than the other? Read on for all you need to know when comparing hydroponics vs aquaponics.
Hydroponics vs Aquaponics
Before we get into the differences between hydroponics and aquaponics, let’s cover what hydroponics and aquaponics are!
Hydroponics is a method of growing plants without soil. The plants receive the nutrients they need to grow through a liquid fertilizer that is added to the water that is delivered to the roots of the plant.
Many benefits come with utilizing a hydroponic grow system in place of traditional agriculture. To name a few: fewer resources are needed to grow, it is highly space efficient, and plants have fast growth rates.
Aquaponics is another method of growing plants without the use of soil. But, it is a bit different from hydroponics.
Aquaponics combines growing plants hydroponically and aquaculture which is raising fish! In aquaponics, the plants do not get their nutrients from an added fertilizer like in hydroponics.
Instead, fish are grown simultaneously in the aquatic environment. A whole symbiotic ecosystem is achieved in a successful aquaponic system.
(You can learn about some popular fish for aquaponics here).
The fish provide the plants with a natural source of organic nutrients through their waste byproducts, beneficial microbes convert the waste into usable nutrient sources for plants, and the plants than naturally filter the water.
All of this together provides a clean living environment for the fish and microbes to thrive in!
While there are some similarities between hydroponics and aquaponics, the addition of fish to the aquaponics systems creates some differences that are important to mention and consider when contemplating a soilless growing system. Continue reading for a breakdown of those differences!
Differences Between Hydroponics & Aeroponics
Hydroponics and aquaponics certainly have their similarities but the fish in aquaponics make the systems very different as well. Read on for the differences between hydroponics and aquaponics that are important to recognize when deciding which system is best for your needs and goals.
System Components
Both hydroponics and aquaponics grow plants in water. But, the depths of that water change between each type of system.
Aquaponics requires space for the fish to move around their environment. Aquaponics call for a minimum of 12” deep grow beds to ensure that the fish have enough room to thrive. But, depending on the species of fish, a certain amount of space will be necessary.
Depths vary with hydroponics, it depends on the type of hydroponic system that you utilize and what that specific technique calls for. For example, deep water culture hydroponics requires much more water depth than ebb and flow hydroponics.
When it comes to supporting the plants, hydroponics generally do the bare minimum. Lettuces and leafy greens are so popular in hydroponic systems because they can be grown in very compact and minimalistic systems. Lettuces and leafy greens do not require the support and substantial growth media that many other plants require.
The microorganisms within the environment of an aquaponic system are crucial therefore it is important to ensure that they are supported. Aquaponics does require some additional TLC for the roots to ensure that the environment is appropriate for the microorganisms.
Start-up & Running Costs
The startup costs of hydroponics systems and aquaponic systems are very similar when you do not include the price of the fish. An aquaponics system requires growing media to harbor the microbes within, which adds a little extra startup cost but generally not a significant amount.
The price of fish is where the systems can vary in cost depending on which types of fish you choose to buy for your aquaponic system.
Plants
Hydroponic systems are very versatile when it comes to which varieties of plants you can grow. Mainly, this is because you can change hydroponic systems according to the needs of the plants.
In hydroponic systems, the plants receive their nutrients from a liquid fertilizer that is manually added to the water which can be adjusted as necessary. Because of this, hydroponics can grow plants with high nutrient needs.
On the other hand, aquaponics does best when supporting plants with lower nutrient requirements like lettuces and leafy greens. This is because the aquaponic system is self-sustaining, meaning that you cannot add additional nutrients for the plants without throwing the entire ecosystem off.
Ecosystem
Hydroponics do not provide an ecosystem for plants because an ecosystem is an environment of interacting organisms that work together.
Hydroponics are simply manipulated and maintained by the gardener themselves. With aquaponics, an ecosystem is established between the plants, fish, and microorganisms.
Maintenence
Hydroponics are not a self-sustaining system because it requires nutrients to be continuously added to the system in addition to other manually added inputs.
In hydroponics, it is important to routinely drain the nutrient solution and replace it with a fresh reservoir to ensure that nothing becomes too concentrated. Yet, it is important to monitor the pH and temperature of both systems.
Aquaponics are self-sustaining systems once the ecosystem is established. Therefore, there is no need to remove and replace the nutrient solution because of the natural cycles of the fish and microorganisms that keep nutrients at appropriate levels.
So, once the aquaponic system is established, there is much less monitoring needed in comparison to hydroponics.
Nutrients
The sources of nutrients are one of the most important differences between aquaponics and hydroponics.
When growing plants hydroponically, the gardener must replenish the nutrient solution routinely. This is done by creating new nutrient-dense water with liquid fertilizer to replace the old water in the system. The nutrients of a hydroponic system can be manipulated as needed by the grower themselves.
For aquaponics, the nutrients are delivered solely by the ecosystem! The waste from the fish is what serves as a source of nutrients for the plants. Therefore, when nutrient levels are low, the fish will continuously provide the nutrients needed to fuel plant growth and support the thriving ecosystem.
Do Plants Grow Faster In Aquaponics?
When initially starting an aquaponic system, it can take some time for the ecosystem to establish itself. This causes debate about which system is faster because aquaponics needs some time before the plants begin thriving.
After creating a hydroponics system, the nutrient solution cycle only needs to run for a couple of days to stabilize before plants are added.
Aquaponics systems, on the other hand, take some time. This is because of the fish that pretty much run the entire system.
It takes at least a month for aquaponic systems to develop the bacteria needed to break down the fish waste. It is very common for systems can take up to 3 months to stabilize themselves and be ready for plants to be introduced.
Once the aquaponic system is up and running, the growth speeds of the plants are very similar to that of hydroponics.
Plants grow faster in optimal conditions which are very easy to create in water-based systems compared to soil-based systems. Water where nutrients are in abundance fuels plants to grow fast and plentiful!
Which Is More Sustainable: Hydroponics Or Aquaponics?
The question remains, is one of the two systems more sustainable than the other? Both hydroponics and aquaponics have clear advantages over soil-based growing: fewer resources are needed to grow, it is highly space efficient, and plants grow at fast rates. But, can one truly be named better than the other?
Many believe that aquaponics is a better option than hydroponics when choosing a soil-less growing system. Fish bring a lot of benefits to the growing system and create an entirely self-sustaining environment.
The system generates nitrifying bacteria that break down the fish waste into a plant-usable source of nitrogen; this is the key to a self-sufficient ecosystem with fish!
Yet, hydroponics is more widely used by hobbyist growers and in commercial agriculture. Hydroponics are easier to set up, have arguably a more aesthetically-pleasing look, cost less, and most importantly a faster return on investment.
When done correctly, plants grow incredibly fast in hydroponic systems from the very beginning. Aquaponic systems take some time to establish their self-sufficient ecosystem before producing those large harvests.
But, it is hard to claim whether one is more sustainable than the other when they are both so incredibly sustainable in their own ways. Much depends on which system will better fit your own needs and how much you enjoy it. Because of this, I don’t think anyone can confidently choose one over the other.
Conclusion
Comparing and contrasting hydroponics and aquaponics is like comparing apples to oranges; they’re both fruit but they have their distinct differences. We do not believe that there is one system that is better than the other. It’s up to you to decide which system will better suit your needs and be more enjoyable.
You can learn about some plants that grow well in aquaponics here.
You can learn about plants that filter water here.
You can learn more about how to create a water garden here.
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~Jonathon
About the author:
Sofi is a passionate writer who studied communications and environmental studies at Eckerd College. You can get in touch with Sofi at https://slenzi4.wixsite.com/website.
