Two big questions a new aquaponics farmer need to ask himself are:
1. What plants should I grow
2. What fish should I use
The topic of aquaponic fish is not as simple as the plants as unlike plants, there are restrictions regarding non-native species so you will need to check with your local fisheries department to see what is available and legal in your area.
There are several different types of fish you can use in aquaponics systems, which is why we have split the topic into 2 separate blog posts…stay tuned for part 2!
Tilapia is the most commonly raised fish in aquaponics because they are very hardy, grow quickly and are popular as a food. They also do well in a mid-temperature water which is compatible with most aquaponics vegetable crops. Having said this, they are highly adaptable and tolerant to varying water temperatures which makes them an excellent choice.
Dissolved oxygen – Tilapia can survive with oxygen levels as low as 0.5mg/L. The ideal range is 3 – 5 mg.L.
Temperature: The ideal temperature is 26.6°C (80°F) , but they will thrive in water that is between 17°C -32°C.
Feed: Most kinds of Tilapia are omnivorous. Usually in large aquaponics systems they are fed a pelleted food which is widely available in most parts of the world.
Hardiness: Tilapia are probably the hardiest of all cultured fish. They can withstand low oxygen,, high ammonia and conditions toxic to other fish. They are also highly resilient to diseases and parasites and thrive in varied water quality conditions.
Growth rate: Under preferred conditions a tilapia can grow to 2.5 pounds in 6 months, this is fast in comparison to most other cultured fish.
The largemouth Bass is more sensitive to imperfect water conditions than tilapia, so farmers wishing to raise this fish need to take special care when monitoring conditions and filtration in the tanks.
There is often strong demand with buyers paying premium price for this fish, so many farmers feel the extra effort is worth it.
Dissolved Oxygen – Levels between 4 – 10mg/L are required.
Temperature – Bass can survive a temperature range of 4 – 32°C (39 – 90°F)
Feed – Young baby bass need to be trained to eat pelleted food. Either a specific bass feed or most trout feeds are suitable.
Hardiness – Bass are also more sensitive to poor conditions than trout or catfish. Things to be mindful of are rough handling, bright lighting and poor nutrition.
Growth Rate – Producing a fish ready for sale takes from 15 – 18 months. If starting with larger fingerlings (from 4-5 inches length) a market-size fish can be grown in 5 – 6 months, if the right conditions are kept.
Also known as bream, brim or copper nose. The name blue gill comes from the bright blue edging on its gill rakers. They can grow up to 16 inches long, and they generally do very well in aquaponics systems.
Dissolved Oxygen – required in the range of 4 – 10mg/L.
Temperature – Blue gill can survive within 4 – 32°C (39 – 90°F). The ideal temperature for growth in an adult fish is about 80°F.
Feed – Pelleted food is to be used from the beginning.
Aquaponics in India will soon be offering consultancy services. Please get in touch for more information.