Have you considered which system you should set up for your garden? Have you been comparing aquaponics vs hydroponics recently?
These two soilless growing systems share many in common, yet they vary in finance, difficulty, materials, and set up.
To decide which is the superior system for your own farming project, it’s recommended that you learn more about their differences.
What are they?
Much to many people’s surprise, hydroponics has been around for 12 millennia and the legendary Hanging Gardens of Babylon was built using its principle.
A hydroponics system comprises of two major parts: the reservoir and the grow beds. The reservoir contains the water mixed with various nutrients while the grow beds consist of the growth media and the plant holders.
In the hydroponics system, the roots of the plants are suspended directly in the water with nutrients needed for its optimal growth. The growth media works as soil in a hydroponics set-up and it can be coconut coir, perlite, rockwool, organic-polymer composites, etc.
Simply put, aquaponics is the combination of aquaculture and hydroponics. It looks like a hydroponic system, but in aquaponics, fish is used to provide nutrients.
In the aquaponics system, the waste from the fishes is converted directly into nutrients needed for the plants by the surrounding bacteria while the plants in turn naturally filter the water, providing a clean living environment for the fish and microbes.
What are their similarities?
These two soilless growing methods share some similarities that include:
As these two systems are typically placed indoors, shielded from the climate and have supplemental lights for growing, you can grow plants all year round even during the off-season. Imagine having juicy strawberries in winter!
Minimized negative environmental impacts
With these two growing methods, your plants will be less susceptible to weed and pest issues. Therefore, your garden will be chemical free, causing no adverse impacts to the environment.
With either of these two systems, your plants will have access to a higher amount of oxygen, which supports nutrient absorption and root growth. In addition, the roots have direct access to nutrients instead of searching for them in soil. All those energies saved will be spent only for the plant growth.
Thanks to the decreased insect pressure and higher amounts of food on a consistent basis, the plants grown in either aquaponics or hydroponics are typically able to yield around 30-40% more than soil-based gardening.
What are their differences?
To choose the growing method that works better for you, it is important to consider the two systems’ differences. It is surprising to see how different it can be by adding in the fish.
System design and/or components
As the aquaponics system needs space for the fish to move around, it requires at least 12” deep grow beds. Meanwhile, the grow beds in hydroponics only need be 6” deep as roots can easily spread out within the aquatic solution.
No extraneous growing media is needed in the sterile hydroponics system while it is vital in aquaponics to harbor the beneficial microorganisms.
The startup cost for aquaponics will be higher as you will need to spend on fish as well as the growing media for the microbes to reside in.
Because of the fish, it also takes longer for the aquaponics system to get functional. A hydroponics system requires a couple of days at most while an aquaponics system might take up to 3 months to stabilize the environment enough to introduce plants.
The running costs for aquaponics are slightly more expensive due to the electricity needed to generate a higher level of oxygenation in the water for the fish. To keep replenishing the nutrient solution, you will also need to regularly add in fertilizers in your hydroponics systems throughout the entire growing season.
It is important to know what you will be planting to choose the one that is more suitable. If your plants have high nutrient needs, choose hydroponics as you can adjust the nutrient solution to meet plant needs.
But if you are looking to grow plant with lower nutrient needs such as lettuce, other leafy greens, and herbs, aquaponics will be a better fit.
Only aquaponics is considered as an ecosystem with its plant/fish/microbe interaction.
Hydroponics is not sustainable as it relies heavily on the nutrients continuously replenished in the aquatic solution.
Meanwhile, minimal inputs is needed in aquaponics as every component is provided within the system and essential for its survival.
In an aquaponics system, the nutrients might be poor but come naturally from the fish waste. However, in a hydroponics system, to create the appropriate nutrient levels, the fresh aquatic solution needs regularly regenerating with fertilizers mixed in.
Monitoring the pH levels is essential in running any aquatic-based growing system. For a hydroponics system, the optimum solution pH should be 5.5 to 6.0.
To safely harbor fish, the solution pH in an aquaponics system should be between 6.8 and 7.0. However, as the waste generated from the fish will create an acidic environment, you will need to keep a close eye on the pH levels.
Electrical conductivity (EC) needs to be monitored closely to make sure your aquatic solutions are safe for the plants to grow and thrive.
In a hydroponics system, salts are naturally present because of the salt-based fertilizers regularly added in. Therefore, the EC levels can get dangerously high, causing damages to the plants. Meanwhile, it is never a concern in an aquaponics system as organic fish waste has very little salts in it.
The water temperature needs to be lower in a hydroponics system to avoid creating a perfect breeding ground for fungus. In an aquaponics system, as fungus is kept at bay thanks to the microbes and fish, the temperature can be higher.
The ideal temperature in a hydroponics system should be below 70°F while an aquaponics system will work the best with the temperature between 82 – 86°F.
Despite lower water temperature and sterile environment, the fungal disease pythium, (a.k.a root rot), still causes headaches for growers in hydroponics.
Meanwhile, pythium is almost non-existent in aquaponics with the presence of the microbes as well as the strong immunity of the plants.
Soilless growing methods significantly solve insect problems. However, you can still notice aphids, spider mites, and thrips in either system. To kill them off, you can easily add in pesticides in hydroponics. But doing so will harm the fish in aquaponics. Therefore, you will need to seek for non-chemical methods.
Once your aquaponics system is stabilized, you won’t need to do much to maintain it apart from checking for pH and ammonia levels weekly or if the fish seem stressed.
But if you set up a hydroponics system, pay close attention to its aquatic solution to make sure the pH levels, the EC, the nutrient concentrations and the total dissolved solids are safe for the plants. Whenever salts become concentrated, drain the aquatic solution and replenish it with a new batch.
This is a bigger problem in aquaponics as the water is filtered much more frequently (every 15 – 45 minutes), which means the system can’t withstand being down for long. In addition, the fish waste can clog the system, making aquaponics solutions more prone to mechanical failure.
Waste disposal isn’t a concern in aquaponics as it is mostly the fish waste not broken down by the microbes and can be safely poured down the drain.
Meanwhile, it is not safe to dump the fertilizer-rich water in hydroponics into natural bodies of water or down the drain.
Which one works better for you?
Both aquaponics and hydroponics offer faster growth and higher yields so it is impossible to decide which is the superior system. It is now up to your preferences, your own needs, your space planned for gardening, your scientific as well as technical expertise to know which works better for you.
If you desire to raise fish and grow crops at the same time, aquaponics seems to be your better fit. But if you wish to set up one that can run as quickly as possible, hydroponic systems might be a better choice.
If maintaining cost is one of your concerns, hydroponics can be expensive due to its chemical nutrients.
Are you still in two minds about which to choose between aquaponics and hydroponics for your garden? Each technique has its potential and it’s important to choose one that will serve you better.
If you are a commercial grower, maybe hydroponics will be a better fit thanks to its precision and control. But if you are more interested in the allure of living creatures, aquaponics seems to be the most ideal. Also, base your decision on the type of plants you will be growing.
About Jill Sandy:
Jill is a sustainable focus gardener at Constant Delights.
She loves decorating her home backyard with beautiful landscape design and creative garden care techniques she develops herself.