Aquaponics and hydroponics, two techniques for cultivating fresh and healthy veggies without the use of soil. Both methods, popular for supercharged yields and year round growth, while quite similar, have some key differences. In this article we look to answer the question of what’s the difference between aquaponics and hydroponics
What is Hydroponics?
Hydroponics is the ultimate method to grow plants without soil. People have been using hydroponics techniques for thousands of years to get a higher yield with less use of soil. This sophisticated system performs better than the conventional way of growing plants in soil.
For the hydroponic system, two things are necessary for plants to thrive: water and a specific set of nutrients. The soil is not needed in the growing system if the nutrients are provided in the water and distributed to the roots. A hydroponic growing system is a nutrient-rich aquatic solution flushed through the plant’s root zone to give them the nutrients required for healthy growth.
What is Aquaponics?
While similar to hydroponics, aquaponics is another cutting-edge method of growing plants without any soil to support their root systems. Hydroponically grown plants and aquaculture (fish farming) are combined to create aquaponics.
In an aquaponics system, plants are grown in a soilless environment, like in hydroponics. An aquatic solution directly delivers the vital nutrients to the plant roots that are required for their growth and where effective nutrient uptake can occur instead of plants acquiring nutrients from soil sources. There are three types of aquaponics: deep water culture aquaponics (DWC), Aquaponics nutrient film technique, and media-based aquaponics.
However, unlike hydroponics, where fertilizers are added to the water to supply nutrients, aquaponics has fish that are simultaneously raised with the plants or vegetables. These fish help to establish a symbiotic relationship with the added flora and bacteria to create an exceptionally effective system.
In aquaponics, the fish naturally provide organic nutrients through their excreted waste, which is then transformed into usable plant nutrients by helpful microbes. The plants then naturally filter the water, giving the fish and microbes a clean environment.
For a more detailed explanation of aquaponics, check out this article.
What do Aquaponics and Hydroponics have in common?
As aquaponics combines the techniques and practices of hydroponics as well as aquaculture, it is natural that there is some overlap between the two. Both are alternatives to traditional soil-based gardening and can return higher yields with the benefit of year-round growth. Able to be set up from your kitchen counter all the way up to commercial greenhouses, many factors are the same in the two systems. Lets explore!
Most hydroponics and aquaponics systems are installed indoors, protected from the climate, and equipped with extra lighting for higher growth. As a result, plants can be grown for much longer than the outdoor season allows.
This enables aquaponic and hydroponic gardeners to produce higher yields all year round to regions that might not have access to it during the off-season(s).
Indoor hydroponics and aquaponics have less chance of getting affected by pests and diseases. These lesser changes cause their higher and healthier production. Moreover, birds and other garden pests cannot transfer the weed seeds from one garden bed to another.
Both approaches involve growing plants directly in water, but because the aquatic solutions are recycled and reused, they require less water overall than conventional gardening. Aquaponics system uses 10% less water than in traditional soil-based farming.
Soilless systems have 30–50% faster plant growth than those buried directly in soil. The idea behind the quicker growth is that the roots in an aquatic solution have more oxygen. This more oxygen promotes faster, more effective nutrient absorption and root growth. The energy saved can also be used for faster growth.
Plants produced in hydroponics and aquaponics systems often have between 30 and 40% more than plants cultivated using conventional techniques. This is partly due to the attentive nutrient monitoring in the aquatic solutions, which ensures plants receive the right amount of food. Still, it is also due to the lowered disease and pest pressure and the more precisely controlled growing conditions.
While there are many similarities between aquaponic and hydroponics. The key difference is how the nutrients are introduced. Whereas hydroponics relies on added chemicals and fertilizers to feed and enrich the plants, aquaponics achieves this by adding fish into the mix.
Bacteria, living in either a grow bed or filter system, break down the fish waste into bioavailable plant food through something know as the nitrogen cycle. This closed circuit process continuously provides food to the plants without the need for any man-made additives. Some more differences are explained below. Read on!
Design and components are the biggest difference in these systems. Hydroponic system require 6″ deep grow beds as roots can easily spread out inside the aquatic solution without any concern for root compaction. While some types of aquaponics system needs will need at least 12″ deep grow bed to give the maximum space for fish to move in.
Additionally, hydroponics systems are sterile; to set up this system, there is no need for another growing medium to nourish the plant roots. Contrarily, aquaponics requires a specific environment around the roots to support the beneficial bacteria.
The startup expenses for aquaponics and hydroponics systems are similar. Growing material is required for the microorganisms to live in the aquaponics system, which raises the initial startup cost slightly. The big difference is the cost of purchasing fish to stock the aquaponics grow beds. The price of fish varies according to the type you choose to raise and the quantity you’ll need.
The discrepancy in start speeds between the two systems is significant. After building a hydroponics system, the nutrient solution must cycle for a few days to stabilize before adding plants. Aquaponics systems take longer to set up and operationalize because of the fish. It takes at least a month for the nitrifying bacteria to grow, and in most systems, it can take up to three months to stabilize the environment sufficiently to add plants.
Aquaponics systems usually best support plants with lower nutritional needs, such as lettuce, other leafy greens, and herbs. Hydroponics growing systems can be utilized for plants with high nutrient needs because the solution can be adjusted to fit plant needs.
An ecosystem is a group of interacting organisms and the environment they create. Due to the interactions between plants, fish, and microbes, aquaponics can be considered an ecosystem, whereas hydroponics cannot.
To be sustainable, something must be maintained constantly without severely harming the environment or depleting natural resources. This leads us to the conclusion that hydroponics is not sustainable since it requires constant fertilizer replenishment in the aquatic solution. Aquaponics is sustainable since it requires little in the way of inputs and comes with every component that is required for the system to survive.
One of the most obvious distinctions between these two systems is the nutrition sources for the feeding solutions. To maintain the proper nutritional levels when growing plants hydroponically, the grower must regularly regenerate new aquatic solutions. Aquaponics has low nutrient levels. However, fish excrement is a natural source of nutrients in the water for healthy plant growth.
The pH of the solution is crucial for any aquatic-based growth system. Aquaponic solutions should be neutral or slightly acidic to safely hold fish, with an ideal pH range between 6.8 and 7.0. Hydroponic solutions should have an ideal pH range of 5.5 to 6.0. The environment will become acidic due to the fish waste, so checking pH levels regularly is critical.
Electrical conductivity is an important factor in aquatic solutions that determines how well a substance will conduct electricity. Any soilless system that relies on its aquatic solution to provide all plant food must test the salts to determine their concentration.
Salts naturally accumulate in hydroponics because growers require salt-based fertilizers to make nutrient solutions. The EC can increase to dangerously high levels during the recirculation of the nutrient solution, harming the plants. This makes it essential to assess EC in hydroponics constantly.
Since fish organic waste contains very little salt, a high electrical conductivity in the aquatic solution is rarely a problem in aquaponics.
Hydroponic systems must maintain a cooler aquatic temperature than aquaponics because fungi can grow in warm temperatures. However, the bacteria and fish in aquaponic systems appear to keep fungus at bay, and the water temperature can be more significant. In hydroponics, it is advised to keep the water temperature below 70°F, while in aquaponics, it should be between 82 and 86°F.
The fungus pythium, also called root rot, is a common issue in hydroponics. Lower water temperatures and a sterile setting help to reduce the incidence but do not eliminate it.
On the other hand, pythium is non-existent in aquaponics. This is believed to be a direct outcome of the aquaponics system’s bacteria and the resultant strength in the plant’s immunity.
Both soilless techniques have much fewer pest issues than planting in soil. In both systems, some insects like thrips, aphids, and spider mites can cause problems, but controlling insects in aquaponics is far more complex. While aquaponic producers must use non-chemical techniques to avoid injuring the fish, hydroponic growers can use pesticides to eliminate insects.
Once the system is stable and operating at its best, growing with aquaponics requires far less monitoring than hydroponics. In hydroponics, the aquatic solution needs to be monitored considerably more carefully to check the EC, pH, total dissolved solids, and nutrient concentrations; in aquaponics, the pH and ammonia levels must be examined weekly or if the fish appear stressed.
Because aquaponics is sustainable and has built-in mechanisms that regulate nutrient levels, there is no need to flush and refill the nutrient solution. As salts accumulate in hydroponic systems, it becomes necessary to periodically drain the aquatic solution and replace it with a fresh batch.
Both systems can experience issues with component functionality, although aquaponics has more of a problem with this. The system can handle being down for a more extended period in hydroponics since the water is filtered considerably less frequently (every 4-6 hours) than aquaponics (every 15-45 minutes). Aquaponics solutions are also more susceptible to mechanical failure because fish waste can cause a clog of the system.
Waste disposal is the last significant distinction between the two systems. As previously noted, hydroponic systems require regular water dumping before adding fresh solutions. In aquaponics, the fish waste is the only element in the aquatic solution that is not broken down by the microorganisms and may be adequately disposed of down the drain. Disposing of this fertilizer-rich water into natural bodies or down the drain can have inherent risks.
The critical question is which system is better. Compared to soil-based gardening, hydroponics and aquaponics have fewer adverse environmental effects, less resource use, faster plant growth, and higher yields.
Many people think aquaponics is preferable to hydroponics when choosing a soilless growth technique. An almost self-sufficient, completely sustainable ecosystem is created when fish are introduced to the system because the excrement is broken down into a nitrogen source that plants may use.
Once an aquaponics system is running smoothly and requires less regular maintenance due to rising salt concentrations, there is no need to replenish or refresh the aquatic solution. It requires less supervision and can be disposed of much more quickly than the aquatic solution from a hydroponics growing arrangement.
However, both commercial farmers and hobbyists use hydroponics more frequently. Because hydroponics is simpler to put up, looks much cleaner indoors, costs less, and—most importantly—has a higher and faster ROI (Return on Investment)
Before use, growers need to carefully know the pros and cons of hydroponics and aquaponics.
So, there is no obvious winner in the argument over which one of the growing techniques is preferable. It will depend on your preferences, goals, and intentions.
Both systems have their own benefits and drawbacks. How to choose a soilless growth method accounts for a lot of the decision. Your needs, finances, level of education, and the products you want to harvest from your system will all be the main factors. Researching each growing method before deciding will help you choose which is ideal for you. For example, if you want to use the aquaponics technique, you must know why aquaponics is important.