What is the difference between aquaponics and aquaculture?

Differences between aquaponics and aquaculture are quite unknown to many, and this results in confusion. There are many differences between the two, and a major one is how aquaponics recirculates the water present in the system. Also, in aquaponics, fish are grown in tanks while you will need bodies of water, such as ponds, for aquaculture.

What is aquaculture?

Aquaculture is the carefully controlled cultivation of aquatic creatures for human consumption. It's comparable to agriculture; however, fish are used instead of plants or cattle. Fish farming is another name for aquaculture. Aquaculture can and does take place worldwide, including in coastal ocean waters, freshwater ponds and rivers, and even tanks on land.

There are primarily two ways of doing aquaculture: freshwater and saltwater. Carps, tilapia, catfish, snakehead, eel, trout, goldfish, gourami, trout, pike, tench, salmonids, palaemonids, and the gigantic freshwater prawn Macrobrachium are all commonly raised species in freshwater ponds. Milkfish (Chanos Chanos), mullet (Mugil sp. ), and several penaeid shrimps are widespread in brackishwater ponds (Penaeus monodon, P. Orientalis, P. merguiensis, P. penicillatus, P. semisulcatus, P. japonicus, and M. ensis). Sea bass, grouper, red sea bream, yellowtail, rabbitfish, and marine shrimps are among the most popular species for aquatic pond cultivation.

What are the different aquaculture techniques?

There are at least three standard methods to do fish farming. These are the following:

Pond systems

The pond system, which dates back thousands of years, is the oldest method of fish farming. Earthen pond, ditch, or canal systems with clay-based soils that may readily be diked to create enclosures are some excellent choices to make up pond farms. If appropriately managed, this aquaculture system brings considerable advantages.

Open net pens

This system is a favorite option among fish growers because of its flexibility, versatility, and scale. They can thrive in any form of water body that best matches their stock's requirements. They are made to let the water run freely through them, which aids farmers in waste management.

Submersible net pens

An alternative to open-net pens is submersible net pens. These structures are entirely underwater and often take the form of a large, closed-off cage. This feature shelters them from the elements and makes them less likely to escape captive fish stocks.

How is aquaponics different from aquaculture?

Here are the differences between aquaponics and aquaculture:

1. Aquaponics is a method of rearing two types of food - fish, and vegetables. On the other hand, aquaculture is solely meant to cultivate fish and other aquatic animals for human consumption.
   
2. Water recirculation is absent in aquaculture since it takes place at various bodies of water. In aquaponics, you are recirculating the water from the fish tank to your grow bed where your plants grow and vice versa. Pumps are installed in the system in order to make this happen.
3. Not much space is needed to perform aquaponics. You can operate your aquaponics farm as long as you have an open space (e.g. backyard, warehouses, commercial spaces, etc.). This feature of aquaponics enables it to be used in places with no functioning agricultural land. Aquaculture, on the contrary, will require much space whether you prefer pond systems, open-net pens, or submersible net pens.
   
4. Aquaponics may be considered as one of the most water-efficient food systems on the planet. According to a study done by the University of Gothenburg, the process of recirculation in an aquaponic unit yields 95 percent to 99 percent water re-use efficiency. Despite the constant use, the system's water quality is maintained, and it only took less than 100 liters per kilogram of fish. This advantage is not present in aquaculture, apparently. To perform any of the aquaculture methods above, you would require an abundant water source.
   
5. Another significant difference between aquaponics and aquaculture is how these two manage the wastes of the fish. In aquaponics, fish wastes are immediately put into use because these are utilized to provide the plants with essential growth nutrients. However, in aquaculture, solid fish wastes are removed and discarded.

What are the pros and cons of aquaculture?

Since aquaculture is an established means of producing human food, it has its advantages and disadvantages. Here is a short list of them:

Pros

1. Aquaculture helps the economy: This system provides enough revenue to assist states, regions, cities, and national governments with funding. Fish is consumed by millions of people in a single country. The total economic impact of aquaculture in Maine, US, nearly tripled from $50 million to $137 million between 2007 and 2014, including sales revenue, full- and part-time jobs, and labor income. Aquaculture enterprises in the state generated $73 million in sales income in 2014.
   
2. Aquaculture provides jobs: Globally speaking, aquaculture has helped people obtain a stable income source. According to the 2016 report of the Food and Agriculture Organization (FAO), there are 18.7 million fish farmers worldwide. This number rises three to fourfold when secondary and postharvest jobs are factored in, as they do with fisheries. Regardless of the scale of the operation, aquaculture activities benefited poor households.
   
3. Aquaculture gives us food: Aquaculture proponents argue that the process is viable to meet the growing demand for seafood and other fish species. Through aquaculture, consumers have a guarantee of a constant supply of food. This also becomes a source of seafood eateries and restaurants, such as prawns, clams, and salmon, among other things.
   
4. Aquaculture helps preserve endangered animals: Overfishing has been a big issue in recent decades. Our wild fish populations have plummeted, and we must safeguard those species for them to recover. One way to conserve those fish stocks is to increase aquaculture production to eat more fish from fish farms instead of wild aquatic creatures. As a result, fish farming could effectively reduce overfishing and protect world fish stocks.

Cons

1. Aquaculture requires much protein: Bestselling farmed fish are carnivorous, such as salmon, bass, and cod. They need a lot of protein to keep up with their rapid growth and energy demands. This protein is frequently produced from small baitfish that have been mashed into pellets. According to a professor from Stanford University, a pound of salmon requires five pounds of fish meal. This is a wasteful conversion rate. It also means that wild sardine, mackerel, anchovy, and other tiny fish species are being targeted, leading to future wild stock collapses.
   
2. Aquaculture encourages invasive species: Although aquaculture provides many benefits for the local ecosystem, it also poses several risks that must be considered. One of the most significant disadvantages of aquaculture production is the increase in invasive species within a specific region. Every ecosystem is a delicately balanced mechanism, with residents working in unison to maintain peace and equilibrium. When non-native species are introduced into a place, this balance is threatened, which can endanger various species.
   
3. Aquaculture leads to environmental issues: One of the most significant drawbacks of aquaculture operations worldwide is the amount of waste generated by the aquaculture systems. It is unfortunate that these wastes are not properly disposed of. Eventually, they contribute to the filth thrown into the seas and oceans. Take, for example, the rise of salmon farms. Salmon is a highly sought-after fish, which explains why there has been a significant increase in salmon farms over the years. Unfortunately, salmon farming has become one of the most significant sources of pollution, particularly in coastal areas. Salmon farm wastes are not properly disposed of and are instead deposited along the coastlines. These pollutants gradually make their way to the seabed's bottom, harming many species living in the area.

This article should have cleared the confusion regarding the differences between aquaponics and aquaculture. Although both are utilized for rearing fish, certain qualities of aquaponics make it distinct from aquaculture. I can even argue that aquaponics has a specific set of advantages compared with aquaculture because it is more sustainable.