To raise salmon in aquaponics, you should closely monitor your water quality within the required parameters to ensure a healthy environment for the fish and plants in your chosen system. Some of the factors you should keep an eye on are the pH range, temperature, and oxygen level. Although salmon aquaponics might be tricky and challenging, the effort you put into it will lead to a productive and profitable yield.
What are the different species of salmon?
There are seven types of salmon in the world. Five are found in North American waters: coho, sockeye, chinook, chum, and pink. The masu salmon is an Asian kind, while the Atlantic salmon lives in the Atlantic ocean. Each has its unique taste, which makes them one of the main ingredients in our health-conscious meals.
Salmon are anadromous, which means they live their entire lives in the ocean yet spawn in rivers and streams. To put it another way, they are born and die in freshwater rivers, but they live in the sea until they reach adulthood.
Why should you farm salmon?
Salmon is nutrient-dense, which is one excellent reason you should consider it as your aquatic animal for your aquaponics setup. Here are some of the possible health benefits of this fish:
- Heart health - Based on a 2016 study, there is a relationship between omega-3 fatty acids and cardiovascular disease (CVD). According to the researchers, by consuming these fatty acids, a person's cardiovascular health might improve.
- Mental benefits - Many of the minerals contained in fish, such as salmon, have lately been linked to lower the risk of affective disorders, such as depression. A 2017 study suggests this.
- Thyroid diseases - A research conducted in 2017 implies that people with thyroid illness deficient in selenium get significant benefits from increasing their selenium consumption, including weight loss and a lower risk of cardiovascular disease and diabetes. Selenium is abundant in salmon.
Which species of salmon is best for aquaponics?
Of all the species of salmon, the Atlantic species is the standard choice to be farm-raised. According to the Washington Division of Fish and Wildlife (WDFW), Atlantic salmon is a "preferred species" for farming in cold marine waters because it grows swiftly and consistently, is disease-resistant, and tasty.
What factors should I consider when growing salmon for aquaponics?
Salmon demands more time and resources from you than most other fish you can farm in an aquaponics system. This is the reason why salmon might give newbies a difficult time. However, if you can provide an atmosphere favorable to their growth and survival, raising salmon will be very rewarding.
Breeding
Salmon are bred in the same manner as trout are bred: milt is collected from the male while eggs are collected from the female. After that, the eggs will be fertilized by combining them with the milt. Water will activate the sperm, allowing fertilization to begin. The eggs will be fertilized and incubated at 39.2 °F - 51.8 °F (4°–11°C) once they have been fertilized. The eggs will hatch in 6-20 weeks.
Stocking Density
The appropriate salmon stocking density is based on a maximum recommended fish mass of 20 kg per 1000 liters. It is critical to remember not to overstock your salmon tank since this will result in a slew of potential issues for your habitat. Consider the estimated size and weight of a fully developed Salmon, even if they are still undersized and immature. Salmon can grow up to 58 inches long and weigh 126 pounds depending on the species (57.2 kg). Now the Atlantic Salmon, on the other hand, can reach 23 and 30 inches long and weigh between 8 and 12 pounds (3.6-5.4 kg).
Room
As you rear Atlantic salmon, a 1000-L tank (264 gallons) is enough to contain four fish, depending on the stocking density. A 20-gallon tank will suffice when starting with salmon eggs.
Feeding
When raising salmon, you should provide different kinds of feeds for each stage of development. The feeds are classified as starter, grower, smolt transfer, seawater grower, and broodstock.
During the seawater growing phase of the production cycle, carotenoid pigments are supplied to the food to produce fish with the flesh color needed by the market.
pH Range
The recommended pH range for salmon is 6.5 - 8.5. Anything below or higher than this would pose problems to the health of your cultivated fish.
Water Temperature
Salmon is a fish that lives in cold water. They prefer cool freshwater throughout their life's stages, so keep the water circulating in your tank and keep the temperature between 55 and 65 °F (13-18°C).
Oxygen
Maintaining adequate dissolved oxygen levels in your aquaponics setup is critical for the health, not only of the fish but of the plants, as well. For salmon, the approved dissolved oxygen (DO) level would be 6.3 mg/L to 8 mg/L.
Saltwater Cultivation
As I mentioned above, salmon are anadromous, which means they dwell in freshwater and the sea. They are born in freshwater, develop at sea, and return to their birth streams to reproduce. Because of this fact, commercial growers of salmon relocate their fish into tanks that contain saltwater where they are allowed to stay until harvest time. However, the Freshwater Institute raised salmon by using freshwater from the beginning to the end of the fish' life stages.
Now, this begs the question, does freshwater salmon taste differently than its saltwater counterpart? Saltwater fish is known to have a richer flavor than freshwater fish, but they also have a salty, or "briny" taste. Freshwater salmon, on the other hand, lack this briny taste and offer a softer flavor profile.
What are the pros and cons of raising salmon in aquaponics?
If you plan on introducing salmon to your chosen aquaponics system, it would be essential to know the advantages and disadvantages of the fish:
Pros
- High market demand - Salmon is still considered a top fish product. In the USA, it is the second most-consumed seafood in the past years.
- Health fish - Salmon is recognized as a good source of essential vitamins and minerals to keep our body healthy and strong. One famous health benefit of this fish is that it keeps our heart healthy since it is rich in omega 3.
- Social fish - Salmon grow well with other fish such as trout since they are of the same fish family.
- Cold fish - Salmon is perfect for countries with cold climates since they prefer swimming in chilly waters.
Cons
- Temperature control - Salmon do not do well with warm temperatures, so you must ensure that your fish tank water is within the cold temperature range that fits the fish.
- Picky eater - Raising salmon might be pricey for hobby growers. Note that an adult salmon is a predatory fish and will eat meat only. Some of their food would be smaller fish, shrimp, and squid.
How to harvest salmon?
Fish are often starved for up to three days before being harvested, though methods vary. The entire procedure is carried out to minimize stress and maximize the quality of the flesh.
In some land-based salmon farms, growers introduce a grader into the fish tank to separate the large. The holes of the grader are large enough for the smaller salmon fish to swim through it, but these holes also keep the big-sized ready-to-harvest salmon from escaping. Heavy-duty dip nets are used to catch harvest-ready salmon.
Many fish are available for aquaponics, including those that are difficult to raise. Salmon is one of them, but you should not fear considering it being added to your fish tanks. By observing the information provided in this article, you can have a good start in raising salmon for your aquaponics setup.
