Commercial aquaculture of this species is a recent activity in Peru and Brazil. As this species is in the CITES II section (strictly regulated and controlled commerce), its aquaculture development must now rely solely on spontaneous reproduction in captivity. Reproduction generally occurs in large earthen ponds where stocks of a few tens of brooders are maintained together at the beginning of the rainy season (December–March in the Peruvian Amazon). Male and female pairs build a nest, delineate a territory and guard the offspring for at least 20 days from other arapaima and/or predators. Spawning in captivity is continuous and some mating pairs can reproduce five to seven times a year, especially when they are isolated in smaller ponds.

Generally the first broodstocks were established relatively recently with fish captured outside the reserved areas, or from reserves that have management plans implemented with the collaboration of the autochthonous populations. These have really contributed to the protection of this species in Mamirauá (Brazil) and Pacaya-Samíria (Peru) natural reserves.

Fry production is presently the principal bottleneck for the development of arapaima aquaculture production. The peculiarities of its reproductive behaviour (territorial mating pairs) and the relatively low fecundity of females make massive fry production difficult and costly.

Adequate broodstock management would normally include the sexing of the brooders but this is difficult with arapaima. No external characteristics are observed during most of the year. Sometimes male jaws are more red-coloured during the reproductive period but this characteristic is not always clear enough to be usable as a routine sexing technique. However, an Enzyme Immuno Assay (EIA) technique has been developed using antibodies to Arapaima vitelllogenin. This antibody has been recently used to develop a ‘sexing-kit’ that can be used directly in the field.

Breeders are usually fed with fresh, frozen or extruded food specially formulated for arapaima, with a high fish protein level (40 percent). Once the mating pair is formed the two breeders are placed in small ponds to allow courtship behaviour and spawning. The fry produced per spawning can vary from a few hundreds to a few thousands, depending on female size and on fry survival. As fry feeding only relies on the natural food present in the pond, the management of plankton production during the reproductive period is a prerequisite to obtain better fry survival. It is also necessary to control fry predators such as birds or other fish species.

The fry produced under these conditions are generally harvested at 7-12 cm (2 to 3 weeks after hatching) and are adapted to extruded food during a period of ~1 month in small tanks using a progressive dry feed substitution through the feeding of small fish and fish meat that has been previously chopped and mixed with ground extruded pellets.

A survey in Peru in 2011 as shown that the average fry production per female and per year ranged from 26 to 1063 depending on broodstock and pond management conditions.

Trials have been performed using freshly spawned eggs obtained from pond bottom nests and incubating them in special baskets (as the eggs are sticky they have to be continuously in movement to get well aerated. The system consists of a 50 cm diameter basket with a plastic net at its bottom (mesh size 1 mm) where the eggs are placed and which is attached to a system that makes the basket go up and down) in well-aerated water. These reports of hatching success are encouraging and this may also increase the overall fry yield per spawning. This system requires careful management skills and generates higher costs but may make the quantity of fry available after each spawning more predictable.

Recently some cases of fry collection as soon as they first appear at the pond surface and their transfer to tanks or raceways have been reported. However, even if this method appears to give improved survival rates, it is necessary to provide Artemia nauplii (combined with natural zooplankton if available) and to progressively supply artificial food.

The following information is based on available rearing information from Perú and Brasil,

Two to three week-old fry collected from reproduction ponds (7-12 cm, 5-10 g) are acclimated to accept dry extruded feed containing 55 percent protein (mainly fish protein); this is generally performed in small rectangular tanks (2x1x0.5 m) stocked at 50-100 fish/m² or in circular tanks (1.5 m³) stocked at 200-250 juveniles/m³. Feed is distributed 4 times a day at 15 percent of BW (Body Weight) ad libitum, using chopped fish fillet mixed with ground dry feed which allows the formation of moist pellets that are ingested immediately by the fish as soon as they touch the water surface. If the pellets sink, they are not consumed and remain at the bottom of the tank. These moist feed pellets are progressively replaced by 2-3 mm dry feed pellets over a four-six week period. The successful level of adaptation generally reaches values of >70-80 percent and the mortality is generally <10-15 percent. During this phase fish are very sensitive to bacterial and parasitic infections, so maximum care is necessary to avoid massive mortalities. After this period the 40-60 day-old juveniles weigh 40-60 g and reach 18-25 cm TL.

These young juveniles are then transferred to small net-cages (10x5x1 m) or ponds (100-1 000 m²) at densities of 5-10 fish/m², fed three times daily with 5-8 mm extruded pellets containing 55 percent protein at a rate of 10 percent of BW. After 30 days the 2.5-3 month old juveniles reach 300-400 g and 40-45 cm TL, with survival rates of >95 percent. At this time they are ready for ongrowing in larger ponds or net-cages.

Net-cages of 300 m³ (10x10x3 m) are stocked at 3 fish/m³ or 1 fish/5-10 m² in 0.5 to 5 ha 1.5-2 m deep earthen ponds. Ponds are not previously fertilized and water exchange is limited to replacing evaporation and seepage losses. Arapaima depends mainly is an obligate air-breathing fish. In ponds as well as in cages. Arapaimas are fed three times a day starting at 5-7 percent BW with extruded floating pellets (containing 45-50 percent protein) of graded sizes that rise to 30 mm at the end of the ongrowing phase. Then the ration is progressively reduced to 1 percent by the 9^th ongrowing month, by which time (12 months post-hatching) most of the fish have reached the marketable size (10-15 kg; 110-120 cm TL) with survival rates >95-98 percent.

Fish are fed with high protein (50-55 percent) extruded pellets for the first 3-4 months and then with 40-45 percent protein feeds for the following months. FCR (Food Conversion Ratio) of 1.7-2.3 have been reported, using feeds from various manufacturers. The cost of a commercial feed that is specially formulated for arapaima in Peru is USD 1.5-2.0/kg and has an apparent FCR ~1.8 to 2.0.

Arapaimas of 10 to 15 kg are generally captured with net seines from ongrowing ponds.

The fish are killed in chilled water, bled and eviscerated. The skin, the head and spinal cord are then removed and the fillets are vacuum packed and frozen. The fillet yield varies between 50-55 percent of body weight.

Presently, production volumes are not sufficient to determine production costs confidently. The cost of 12 cm fingerlings from small local producers is USD 3-4 for those that have not yet been adapted to artificial extruded feeds.