Tilapia
Which Tilapia to choose?
Blue Tilapia
Is a good choice for aquaponics as it withstands the cold well
Redbrested Tilapia?
Here’s everything you need to know about the Red Breasted Tilapia:
https://www.aquafarmbuddy.com/is-rendalli-red-breasted-tilapia-the-best-fish-for-aquaponics/
Tilapia Benefits
Following benefits makes them one of the ideal candidates to use in aquaponics.
- Adapt very well to tanks
- Can be “crowed” in very high stocking densities (3/4 lb/gallon) within the fish-tank part of the system
- Tilapia have a very efficient feed conversion ratio (1.3-1.8 lbs feed/lb fish)
- Good dress out percentage (86% with head, 66% without head, and 33% fillet)
- They adapt to their environment and are able to withstand less than ideal water conditions.
- Tilapia grow fast and can reach from fingerling size (50 g) to maturity (600 g) in about 6-9 months.
- They’re interesting to watch in the tank due to their rapid and frequent breeding.
- Tilapia culture is also profitable on small-scale outdoor ponds. (variables include market price, feed costs, survival rates, technical ability, and geographic location)
- Market acceptability & recognition and low production costs (Ponds: 51-60¢/lb, Tanks: $1.51-1.79/lb).
Water Quality & Temperature
Although tilapia is considered a freshwater species, it can live in brackish conditions. They are so tolerant of poor water quality conditions that they are often farmed in facilities where other fish would just die. They are a great choice for beginner aquaponics because they handle different water conditions from temperature, pH, nutrient, oxygen levels and more.
Tilapia can tolerate temperatures extremes of 14 and 36 °C for a breif period of time but they stop feeding or growing below 17 °C, and die when it drops lower than 12 °C. The ideal range to ensures good growth rates is 27–30 °C.
They are immune to many parasites and pathogens. They also handle the stress very well. However, for optimal growth and health this species, like most others, prefer DO >6ppm; pH>6; and low ammonia and nitrite levels.
Uses
Tilapia ranks fourth on National Fisheries Institute’s top list of the most consumed fish and seafood in the United States. During 2010, the average consumption of tilapia was nearly 1.5 pounds per person because they are a great source of protein. Their mild flavor makes them adaptable to many culinary styles.
They are produced in outdoor ponds as well as indoor systems for sale as live food fish to the restaurant and supermarket trade. These artisanal and commercially cultured fish is also becoming increasingly popular in many European countries.
Feed
Tilapia are omnivores and will eat just about anything from microscopic organisms through their gills, (they literally “filter” them out of the water), to algae, weeds, vegetable scraps, bugs, worms, tadpoles, etc. They also eat many alternative feeds like duckweed, Azolla spp., and other high-protein plants which makes them important in aquaculture. During breeding, they eat their own young juvenile, therefore, they need to be separated by size.
You can feed Purina line of Tilapia food called Aquamax Catfish and Tilapia. They do not have high protein requirements. Any regular pellet pond fish food that is high in vegetable protein is alright to use. Some people even feed them cat food (Iams kitten dry food is best), if nothing else is available.
Spawn
It is easy to breed tilapia in small-scale and medium-scale aquaponic systems. Healthy broodstock fish are hand-selected for breeding and are not usually harvested. The optimal ratio i.e. 1 male for 3-5 females encourages the spawning. Females may spawn every seventeen days, especially when water is warm, algae-filled and shaded, well oxygenated (>8.0 ppm), and in a calm environment.
Tilapia are mouthbrooders and hold their eggs in the mouths. During this time, the mother stops eating and should be separated from the male. Two smaller separate fish tanks can then be used to house the broodstock and juveniles. Mother will release fry when they start free-swimming after yolk sac disappears.
Fry are kept in a separate tank to avoid the larger fingerlings cannibalize them. The eggs and resulting fry are maintained at a temperature of 80°F to 84°F and pH of 7.5 to 7.8. You can also use small aquaponics tanks to maintain the water quality and temperature.
Here is a video of Tilapia mother releasing fry out of her mouth.
Some fish farms only keep the males because they grow larger in size at a faster rate. The male doesn’t spend energy to develop ovaries or stop eating during spawning, unlike females.
Sexually mature males and females in the same tank can drive competition for food because of continual fry production. Hormone treatment or hand sexing of fingerlings can yield monosex male tilapia. Testosterone-enriched feed increases the hormone levels in the blood and reverses the sex in female fry during their first three weeks of life. This is an efficient way to stock same-size male tilapia in ponds to avoid any problems of spawning and stunted growth by feed competition from the newer fry.
Regulations
There are many regulations on importing, exporting, and keeping tilapia in many states throughout the world.
The adaptable and productive tilapia can easily turn into a problematic invasive species. Tilapia production in outside facilities is strictly regulated to avoid unwanted introductions and environmental damage to native fresh-water systems, particularly to sport-fishing resources.
So it is important to prevent escapes and adhere to local regulations. So check the regulations with your state fishery department before ordering.
They are banned throughout Australia (except WA) due to their ability to overtake local waterways.
Challenges
Tilapia needs warm water and may not be appropriate for winter seasons unless you have a good fish tank heater to maintain the temperature of water. In temperate climates, you can grow tilapias during the warmest seasons (they are fast growing!) and switch to carp or trout during the winter. For cold areas, you rather should consider choosing a different aquaponics fish species that is well suited for your temperature range.
Their rapid breeding needs to be controlled for various reasons. They can quickly fill a small system with schools of young fish, spread juveniles to the whole system and disrupt the operations of settling tanks or nibble roots of floating raft systems. Male tilapia are usually kept because the females stop eating during breeding which is not good aquaponic plant production. They also need to be stocked at high densitiesbecause males get territorial and aggressive in low densities. Hence, You will need to have separate tanks for the female, male, breeding and juvenile.
Some people complain of off-taste of Tilapia. They taste great when they grow in a clean and well managed aquaponic system with adequate dissolved oxygen and are fed a high-quality feed.
Tilapia is also a declared pest in various places. Watch for your local wildlife regulations!
From: https://www.leaffin.com/tilapia-aquaponics/
Breeding Tilapa
https://www.youtube.com/watch?v=YuXd5ahNir8&list=WL&index=12
Growing our own Fish Food
We can grow all our own fish food.
Youtube Video on producing Duckweed and Maggot
Duckweed
We can grow duckweed so as to sequester Nitrogen from the air and create a rich staple diet for our fish. This is the entry point where Nitrogen enters our Aquaponics cycle, much like nitrogen fixers are used in Permaculture.