Those who’ve been doing some research on the science of agriculture and the best ways to grow plant and animal life might’ve often come across these terms. Aquaculture and aquaponics may seem very similar at first glance, but upon deepening your understanding of each, the differences begin to become a lot clearer.
Aquaculture involves raising aquatic animals or plants in a controlled environment. While these animals and plants might be raised by the same person, they’re usually raised independently of each other.
On the other hand, aquaponics raises aquatic animals and plants in a symbiotic system. In essence, aquaponics depends on a symbiotic system to run while aquaculture does not.
If you’d like to learn more about both of these systems, as well as the differences between them, then read on!
What Is Aquaculture?
Aquaculture is the more popular of the two concepts I’ll cover in this article. It provides a significant amount of the world’s edible fish population and is a preferred and sometimes cheaper alternative to conventional farming.
Aquaculture is the practice of raising aquatic organisms. A more comprehensive definition is the cultivation of fish, plants, crustaceans, algae, and other aquatic life under controlled conditions to maximize output.
Essentially, aquaculture is any form of animal production that involves only aquatic life. This feature is what differentiates it from other occupations that rear animals.
It is also important not to confuse aquaculture with fish farming. This confusion is understandable but not completely accurate.
Fish-farming is a type of aquaculture where fish are the only aquatic life being raised. This clause differentiates it from aquaculture, which allows any aquatic life to be raised regardless of species.
What Is Aquaponics?
Aquaponics, although the lesser-known of the two, is no less valuable. It is a great way to merge two areas of agriculture (aquaculture and hydroponics) to maximize efficiency.
Aquaponics is the symbiotic culture of plant and aquatic life. For a system to be considered an aquaponic system, it must have three elements; aquatic animals, plants, and microorganisms. All three elements function together for the sustainable growth of the system.
The animals you choose (usually fish) produce waste that, along with water, passes through the microorganisms to be “filtered.” The filtered water is then passed back to the fish tank, and the entire process starts again.
Differences Between Aquaponics and Aquaculture
Now that we know the exact definition of each and what they involve, it’s a lot easier to point out the differences between them.
However, to understand the differences between both terms completely, you must understand the elements of each and how they differ:
Scope
The first element that differentiates aquaponics and aquaculture is their scope. Aquaculture is focused primarily on the rearing of aquatic life, usually raised for sale.
On the other hand, aquaponics is the merging of aquaculture and hydroponics to create a symbiotic environment. It is the development of an aquatic system in which plants, animals, and beneficial bacteria coexist and depend on each other for survival.
As you can see, the scope for each system is slightly different.
Types
The categorizations that these systems can be divided into are also a key difference between the two. Although there may sometimes be some overlapping, usually both areas use vastly different categorizations to raise fish and plants.
Types of Aquaculture
Starting with aquaculture, there are a lot of characteristics to go through. A quick Google search will give you many varieties when it comes to the discipline. However, listing them all would be near-impossible, as endless variations exist due to differences in location and cultural traditions.
For simplicity’s sake, you can divide aquaculture into two broad categories:
- Extensive systems
- Intensive systems
Extensive Systems
The extensive system of aquaculture has a very loose definition. Generally, extensive agriculture is usually low in labor requirements and economic costs.
Rather than setting up a specialized area for raising aquatic life, people who practice extensive aquaculture will usually cordon off an area of an already existing water body.
Doing so is a great way to keep costs down and minimize the amount of work you have to do. It can also positively affect the ecosystem if you do it well. Setting apart a safe space within the larger ecosystem can promote animal health and improve the overall quality of life available in the water.
Conversely, extensive systems also have their downsides. The sheer size of them is one of the most damaging factors, as extensive systems being open to the elements is a double-edged sword.
On the one hand, they vastly reduce the amount of work you have to do to maintain optimal conditions. On the other hand, not being in complete control of environmental conditions means that your fish are usually vulnerable if there is a sharp change in weather, sunlight, oxygen levels, etc.
This exposure can also leave them open to predators, significantly reducing their population.
Intensive Systems
Intensive systems lie on the other side of the coin. A good way to think of it is to look at the overall act of aquaculture as a system of inputs that give you your product (output). Think of the inputs as things like sunlight, water, food, oxygen, and everything else that your fish need to survive.
Once you can visualize this, think of an intensive system as one where you have to provide the majority of these inputs to get your product. As a result, you can say an intensive system is one where you’re responsible for most of the conditions that your fish need to thrive.
As a result, to keep an intensive system running at optimal efficiency, you need to account for each condition and keep them at optimal levels. While it is impossible to bring the sun into your enclosure and shine it on your fish, it is possible to find substitutes.
This sort of substitution is the basis on which intensive aquaculture is based. For example, many people use artificial light sources like fluorescent or incandescent lamps to replace sunlight. Similarly, you would use liquid oxygen or an oxygen tank to replace oxygen produced from plants.
Types of Aquaponics
Similar to aquaculture, there are also two broad categorizations of aquaponic systems. However, unlike aquaculture, both types of systems require enough work that they are both considered intensive methods. Instead, they differ on the scale of the operation.
Backyard Aquaponics
Like extensive systems in aquaculture, the backyard aquaponic environment is relatively common and far easier to set up than its counterpart. Smaller-scale elements and less capital usually characterize backyard aquaponic systems.
Most backyard systems are built to provide for a single person or their immediate family and/or friends. This difference is key in differentiating backyard systems. At first glance, it might seem like a backyard system is simply the aquaponic form of an extensive system.
However, there are some key differences.
First, it is far more common to have people build backyard systems for self-production rather than commercial purposes.
Secondly, although backyard and extensive systems both require less capital and labor than their counterparts, there is still a huge difference when you compare them directly. A beginner backyard system will usually cost you upwards of $2,000. In contrast, a basic extensive system would cost significantly less.
Commercial Aquaponics
Commercial aquaponics cover a wide range of systems. Unlike backyard systems, their commercial counterparts are usually far more intensive and require more investment and labor.
As different as they are from the backyard systems, they’re even more different from aquaculture environments. Commercial aquaponics systems are large, intensive projects with various bells and whistles to keep the processes running.
Methods
As the types of each differ, so do the methods. Efficiency is the goal of both systems, and the majority of the methods are built with this in mind. However, due to their different approaches, maximizing efficiency is achieved through different methods here.
Aquaponic Methods
Aquaponic methods are centered around both production and efficiency. While maximizing productivity is very important, it is similarly important to ensure the system is as efficient as possible.
For aquaponics, where there are so many other factors that need to be considered along with productivity, finding the proper balance between each part is extremely important.
Raft
The raft system uses thin polystyrene boards as a mechanical support for the plants. They act like rafts because they float on top of the water and keep the plants from getting entirely submerged.
In turn, the plants grow on the top of the rafts, with their roots growing below the rafts partially or fully submerged in water to gain nutrients from it.
The raft system is by far the most popular method in terms of productivity. Compared to the other two methods, it outdoes them significantly when producing in commercial quantities as it is the most scalable of the three.
However, it also has downsides. For example, because of the nature of the method, quite a lot of water is required to keep it running.
This condition raises two problems.
First of all, a large amount of water has to have a proportional amount of fish to keep it running. More fish means higher costs, raising the overall cost of running the system.
Secondly, keeping it at the proper temperature can sometimes be expensive because you need so much water. Plants need an optimal temperature to do well, and without this, many of your plants might falter or, in extreme cases, die.
As a result, if you have particularly nasty winters or overall cold weather year-round, a raft system might not be the best option for you due to heating costs.
Media-Filled Beds
If raft systems are the king of commercial aquaponics, the media-filled systems are the king of backyard aquaponics. Although good for commercial use, raft systems are far too complex if you want a simple backyard system.
Media-filled systems are a type of aquaponic system where the planting area is filled with media like gravel or perlite. This media serves as both physical and biological support for the plants.
The grow bed where the plants and media are, is filled with water and emptied intermittently to provide nutrients to the plants and purify the water for the fish.
Of the three on this list, this method requires the least input and capital, making it optimal for beginners and hobbyists. However, if you eventually plan to grow on a significantly larger scale, you might have to change your entire system to a raft or nutrient-film system.
Media systems simply don’t scale well commercially, as the cost and complexity of making grow beds filled with different media on a large scale is simply not worth it.
Nutrient-Film Technique
Also called the NFT system, this technique of growing aquaponic plants uses long channels in rows. These channels house rows of plants and have a constant stream of water running through them from the tank. This water forms a flowing “film” of plant nutrients which is where the method’s name comes from.
The major downside of the NFT system is that it can sometimes be more difficult to run than the raft and media systems.
For example, clogging can become a serious problem because the water is running through relatively slim channels. Also, this system requires constant water flow to function. As a result, interruptions like power outages can cause significant problems to plant life if not handled quickly.
Aquaculture Methods
While efficiency is also important in aquaculture, productivity is far more relevant. The difference in dynamics makes it easy to focus on productivity as long as the system is relatively efficient.
Looking at aquaponic systems, you can see a trend between them that ties it all in. The raft, NFT, and media systems all have a general theme of balancing each part of the system to ensure the load is evenly distributed.
In contrast, aquaculture systems do not have to worry as much about balance. That isn’t to say that these systems are inefficient. Rather, because these systems are set up with only one component (fish) to worry about, there is less focus on balance and more on functionality and production.
Pond System
The pond system is extremely basic but is also one of the most popular aquaculture methods. This method involves separating specific areas in existing ponds for rearing fish.
Usually, the fish used are are found on the aforementioned pond. However, they are separated from the rest of the pond wildlife using an enclosure like a net or cage.
The pond system is particularly popular in developing countries for its low capital-high return dynamic. Usually, the type of fish used here are freshwater species, like tilapia and catfish. Fish feed is also usually natural, with the farmer leaving the fish to feed on naturally occurring prey in the pond.
Open Net Pens
Open net pens are another form of extensive aquaculture. However, unlike pond systems, this method is usually done in saltwater habitats. Although the habitat is larger, this method is usually a lot more intensive than pond systems because you have to carefully manage the living conditions of the fish.
Like the pond systems, the managed fish can either be catched from the same habitat or introduced from external sources.
One major downside is the amount of exposure here. Similar to pond systems, the fish are exposed to a wide variety of environmental conditions. However, because the habitat here is so much larger, there is a significantly higher chance of problems like disease outbreaks and predators.
Open net pens are also considered an environmental risk, as the free exchange between the pens and the surroundings can be problematic.
Recirculating System
Of all the methods mentioned so far, the Recirculating Aquaculture System (RAS) is the most similar to a standard aquaponic system. The RAS employs equipment to purify used water and recirculate it through the system.
This system is highly intensive, and unlike the other alternatives mentioned here, it usually takes place fully indoors and under very controlled conditions. Also, it bypasses a lot of the other problems faced by extensive systems like diseases and predators. Because water is constantly being recirculated through the system, the total required amount is kept to a minimum.
However, the constant need for recirculation means there is also a need for constant electricity to keep the system running.
Goals
Of course, the goal of both systems is to maximize output. However, how they arrive at this point is different for each system.
For an aquaculture system where producing fish is usually the main goal, harvesting as many fish at the end of a cycle is the most important thing. Generally, the more fish you have in the system, the better.
However, the goals and methods of achieving them for an aquaponic system are slightly different.
First of all, the goal of an aquaponic system is not always to produce as many fish as possible. Sometimes, the fish are simply a means to an end, with the plants being the main goal.
Also, having a lot of fish is not always ideal in an aquaponic system. Unlike aquaculture, aquaponic farmers usually have to worry about equilibrium and production.
The entire aquaponic system hinges on how well each part (plant, fish, and bacteria) perform their duties. Because of this, having a surplus of one can increase the burden on another sector, and if not managed properly, the entire system could fail.
For example, the recommended stocking rule for fish is two fish per gallon (3.79 L) of water. If you were to pass this rule significantly, the increased amount of fish would lead to a corresponding increase in fish waste.
This waste then passes to the biofilter, which might not handle the conversion load well. The unfiltered water then goes to the plants, which also cannot handle the corresponding load, and then the cycle repeats until failure.
Longevity
Aquaculture has been around for centuries. Farmers have practiced raising fish for sale and consumption from time immemorial.
In contrast, aquaponics is the new kid on the block. Although there is some history of it being practiced indirectly centuries ago, the deliberate practice of aquaponics is only about 50 years old.
As a result of the difference in time frames, aquaculture has had far more time to solidify itself as the method of choice for most agriculturists. Currently, it accounts for over 50% of all produced seafood.
The difference also means that there are many more optimized methods for aquaculture than aquaponics.
That said, aquaponics is an underdog that punches well above its weight. Although it is a newer, less tested idea, it does well to prove itself.
Biological Life
The final difference between aquaponics and aquaculture is the amount and type of biological life present in the system.
The main type of life present for aquaculture is usually animals (fish, shrimp, etc.). As the ultimate goal here is fish production, you usually do not have any other aquatic life but them in the system. An exception can be made for extensive systems where a lot of the food can sometimes be naturally occurring.
On the other hand, aquaponic systems have to balance three things: fish, plants, and microorganisms. You must properly manage each to ensure that the overall system is balanced.
| Difference | Aquaponics | Aquaculture |
| Scope | Symbiosis between hydroponics and aquaculture | Raising aquatic life only |
| Types | Backyard aquaponics Commercial aquaponics | Extensive aquaculture Intensive aquaculture |
| Methods | Raft system Media-filled beds Nutrient-film technique | Pond system Open net pens Recirculating system |
| Goals | Balance between efficiency and output | Majorly focused on output |
| Longevity | About half a century | Centuries |
| Biological Life | Always has plants, animals and bacteria | Majorly focused on animals (usually fish) |
Which Is Better: Aquaponics or Aquaculture?
Having read through all the differences between both, you may now be wondering which system is better. This topic is quite polarizing, and there is a lot to recommend in both systems.
Aquaponics is better if you want to produce a mixture of fish and plants. Aquaponics is also a better choice if you’re a hobbyist because once you learn proper practices, it can be self-running, with maintenance being the only issue.
However, aquaculture is better if fish production is your only goal.
Both sides have a lot of positives and a corresponding amount of negatives. That said, aquaculture is usually the more popular option, although aquaponics has begun to catch on a lot more recently.
Final Thoughts
Aquaculture is the most popular way of producing fish for consumption today. It also has a lower barrier to entry than aquaponics and is usually more accessible for fish production.
On the other hand, aquaponics balances fish and plant production very well. Although it is a relatively new area of agriculture, it is quickly catching steam, and many farmers have started to adopt it as a valid means of production.
Both disciplines are highly sought-after choices and which one you choose depends entirely on your needs.
