Fish farms or fish farming is a form of aquaculture. The act of fish farming is about raising fish commercially in tanks or enclosures for human consumption. There are different types of fish farms that utilize different aquiculture methods.
The first method is the cage system which use cages that are placed in lakes, ponds and oceans that contain the fish. This method is also widely referred to as off-shore cultivation. Fish are kept in the cage like structures and are “artificially fed” and harvested. The fish farming cage method has made numerous technological advances over the years, especially with reducing diseases and environmental concerns. However, the number one concern of the cage method is fish escaping and being loose among the wild fish population.
The second method is irrigation ditch or pond systems for raising fish. This basic requirement for this method is to have a ditch or a pond that holds water. This is a unique system because at a small level, fish are artificially fed and the waste produced from the fish is then used to fertilize farmers’ fields. On a larger scale, mostly in ponds, the pond is self-sustaining as it grows plants and algae for fish food.
The third method of fish farming is called composite fish culture which is a type of fish farming that allows both local fish species and imported fish species to coexist in the same pond. The number of species depends, but it is sometimes upwards of six fish species in a single pond. The fish species are always carefully chosen to ensure that species can coexist and reduce competition for food.
The fourth method of fish farming is called integrated recycling systems which is considered the largest scale method of “pure” fish farming. This approach uses large plastic tanks that are placed inside a greenhouse. There are hydroponic beds that are placed near the plastic tanks. The water in the plastic tanks is circulated to the hydroponic beds, where the fish feed waste goes to provide nutrients to the plant crops that are grown in the hydroponic beds. The majority of types of plants that are grown in the hydroponic beds are herbs such as parsley and basil.
The last type of fish farming method is called classic fry farming this method is also known as “flow through system”. This is when sport fish species are raised from eggs and are put in streams and released.
There are a number of different fish species that are raised on fish farms, the most common fish spices raised are salmon, carp, tilapia, catfish and cod.
Catfish are easy to farm in warmer climates. Catfish are predominantly farmed in fresh water ponds and fed mostly soybeans, corn and rice. Catfish are often considered one of the more sustainable fish specifies for fish farming purposes. Cultivating catfish first began in the 1900s and became commercialized in the 1950s. Catfish is populous because of its health benefits and market demand. Farm-raised catfish are usually harvested at 18 months of age where as wild catfish usually get much bigger. There are a number of catfish species, but the three most prominent ones are blue catfish, channel catfish, and flathead catfish.
Tilapia is the third most popular fish used in fish farming or aquaculture, with the first two being carp and salmon. They have increased in popularity due to their high protein, large size and growth capabilities. Tilapia is a tropical fish that requires warmer water to survive. The ideal water temperature is usually between 28 to 30 degrees C. Tilapia fish are known to reproduce rapidly and this is a challenge for managing tilapia fish species for farming use. If not managed properly, fish will aggressively compete for food which may result in stunted growth. Therefore, males are almost used exclusively. Tilapias are resilient towards fighting off diseases and parasites. Tilapia fish farming originated in Africa and is popular in Honduras, Papua New Guinea, Philippines and Indonesia. Tilapia fish require a cereal-based diet and don’t eat other fish, but they are also considered to be one of the most invasive fish species.
Salmon is one of the most popular fish species with the most commonly farmed being Atlantic salmon. There are two other varieties of Pacific salmon that are also farmed – Chinook and Coho. Farmed salmon are vaccinated to prevent disease outbreaks and only on rare occasions do they require additional medications. There are often questions about the different colours between wild and farmed salmon – farmed salmon aren’t dyed, their colour comes from their food. Salmon feed is made to conserve wild fish stocks.
Tuna fish are saltwater fish and are important in the commercial fish farming industry. Japan is the biggest consumer of tuna and has invested a significant amount of research into studying the fish. There are different species of tuna including, bluefin, yellowfin, and albacore. Bluefin tuna populations have dropped significantly in some regions due to over fishing. Farming tuna is complex as the fish are “massive” and are very active - so simulating their natural environment is extremely difficult. Most tuna for human consumption are caught in the wild and raised in a facility to increase weight gain. Tuna are carnivorous and eat other fish. Tuna are typically farmed in net pens offshore and in some cases are farmed in recirculation systems.
Eel fish farming emerged in the early 1950s and it is considered one of the most profitable in terms of export value in the fishing industry. However, the profit value is largely driven by the Asian markets and is culture specific. Eels are a carnivorous and catadromous fish, which means that when they are young they live in fresh water, but as they mature they migrate to the sea for breeding –spending anywhere from 8 to 30 years in freshwater before they migrate. The majority of eel farming takes place in Asia, with China, Japan and Taiwan leading as the biggest producers. Glass eels are preferred over elvers because they are easier to transport and wean onto artificial diets. Eel farming can take on one of two different forms – high intensity recirculating tank (indoors) or intensive pond facilities.
Aquaculture is also known as “aqua farming” which relates to the farming of aquatic organisms such as fish. The farming aspect of aqua farming implies some aspect of intervention into the natural growing process to enhance production. According to the United Nations’ Food and Agriculture Organization – aquaculture has grown three times faster compared to land-based animal agriculture.
Fish farming supplies
Fish farming supplies are needed for the aquaculture industry. The supplies can range from feed and feeders, filtration systems, hatchery supplies, heating and cooling systems, lighting, hydroponics equipment, pluming, predator control, tanks and water treatment products just to name a few.
Feed and feeders Feed quality is important in fish farming and is vital to fish health. Depending on the feed that is given, it can help with desirable colour, growth and overall health and well-being. There are a wide variety of different feeds that are suited to different types of aqua-farming methods and species.
Water Filtration Systems Water filtration systems are important when attempting to mitigate environmental impacts. Filtration involves the removal of waste products from the water. There are a number of different types filtering systems that can be used, but it often depends on the state of the filtration process. It is important to have a staging filtration system that will ensure most optimal results.
Hatchery supplies Hatchery supplies include anything from fish graders, shipping supplies to spawning and handling containers.
Predator control Predator control tools are used in the fish’s habitat, which often includes the use of physical deterrents which may include visual and audio deterrents.
Indoor fish farming
Indoor fish farming is the alternative to cultivating fish outdoors in a cage system. With the emergence of technological advances, raising fish indoors is now possible using proper control production methods. Indoor fish farming is often very sophisticated and in some cases allow for automatic collection and processing of fish wastes into crop fertilizers. There are advantages and disadvantages to indoor fish farming:
Advantages to indoor fish farming
- Fish are protected from predators and weather changes.
- Fish are often produced faster through temperature control, water quality and feeding practices.
- Indoor fish farming is often considered more environmentally friendly because it requires less water and produces less waste.
- Avoids the chance of fish escaping and getting loose amongst wild fish populations.
- Allows higher stock densities and often saved farm labour input costs.
- It often allows greater flexibility for facility locations, which can save transportation costs if facilities are located near markets.
Disadvantages to indoor fish farming
- Requires electricity input costs.
- Requires infrastructure set-up which often requires a significant amount of startup capital.
- Fish raised indoors are carnivorous, which requires the capture of large amounts of other fish for their diet.