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Inputs, outputs, and accumulation of phosphorus were evaluated for monoculture and polyculture grow‐outs of the Amazon river prawn, Macrobrachium amazonicum and tambaqui, Colossoma macropomum in stagnant earthen ponds using a hypereutrophic water source. A completely randomized experiment was designed with four treatments and three replications: prawn monoculture—monoculture with 30 prawns/m2, fish monoculture—monoculture with 3 fish/m2, integrated multitrophic aquaculture (IMTA)—polyculture with 30 prawns/m2 and 3 fish/m2 reared free swimming, and POLY‐CAGE—polyculture with 30 prawns/m2 and 40 fish/m3 reared in net cages. Samples of commercial diet, water, rain, animals, accumulated sludge, total suspended solids, and settleable solids were collected throughout the experiment to determine the total phosphorus contents of the inputs and outputs and to calculate the phosphorus budget. Results showed high variability in the phosphorus content of each variable in all treatments. Much of the phosphorus was accumulated as solid material at the bottom of the pond (ca. 31–73%). The integrated grow‐outs showed the best phosphorus conversion from the commercial diet (ca. 24–34%) and phosphorus use efficiency from all inputs (ca. 12–18%). Bioturbation from both species appeared to influence the liberation of phosphorus to the water column, stimulating plankton productivity and promoting the turnover of nutrients. A mud‐feeder species should be added to the IMTA systems to take advantage of the large amounts of nutrients in the bottom sediments and increase the uptake of phosphorus by the farmed species. [ABSTRACT FROM AUTHOR]

This work determined the nitrogen inputs, outputs and accumulation in compartments of stagnant earthen ponds for the monoculture and integrated multi‐trophic aquaculture (IMTA) of the Amazon river prawn (Macrobrachium amazonicum) and tambaqui (Colossoma macropomum), using recycled hypereutrophic water. A completely randomized experiment was designed with four treatments and three replications: PM–monoculture with 30 prawns/m2, FM ‐ monoculture with 3 fish/m2, IMTA ‐ polyculture with 30 prawns/m2 and 30 fish/m2 free, POLY‐CAGE ‐ polyculture with 30 prawns/m2 free and 40 fish/m3 in net‐cages. Animals, rain, water, feed, soil, gas, accumulated sludge, and suspended sediments were collected throughout the experiment to determine their nitrogen contents and to calculate the nitrogen budget. Results showed that much of the nitrogen available escapes to atmosphere as N2 (~40%–56%) after denitrification or accumulated within bottom sludge (~14%–42%). The remaining nitrogen was converted in animal biomass (~5%–21%) or was discharged to receiving waterbodies in the outlet water (~11%–13%). Feed management appeared to influence the major biological processes in the aquatic nitrogen cycle, such as photosynthesis and denitrification. The fish‐prawn IMTA systems converted approximately 53%–75% of feed nitrogen into harvestable products, which is more efficient than the 19%–46% of feed nitrogen converted in the monocultures. However, a large amount of nitrogen is accumulated in the pond bottom in all systems. An increased prawn density or the addition of a mud‐feeder species to the culture may enhance the incorporation of this material in harvested biomass, improving the efficiency of the systems. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the feasibility of producing the Amazon river prawn (Macrobrachium amazonicum) with tambaqui (Colossoma macropomum) in integrated multi-trophic aquaculture (IMTA) systems. An experiment was carried out in a completely randomized design with four treatments (types of production systems) and three replicates per treatment (ponds): prawn monoculture (30 prawns. m−2); fish monoculture (3 fish. m−2); IMTA with prawns and fish free-swimming in the same pond (30 prawns. m−2 and 3 fish. m−2); and IMTA with prawns free-swimming and fish in cages placed inside the ponds (30 prawns. m−2 free-swimming and 40 fish. m−3 in net cages). Prawns and tambaqui in the monocultures received commercial pelleted diets, whereas only the tambaqui received the pelleted diet in the integrated cultures. The experiment lasted 5.7 months. Both the prawns and the fish developed well in stagnant ponds while using nutrient-rich water. The mean final body mass, final body length and productivity of the prawns in the monoculture were higher than those of the prawns in the IMTAs. No significant differences were observed for the survival of the prawns and the tambaqui between treatments, and for the mean final mass of the tambaqui between the monoculture and the IMTA systems. Prawn growth and yield were similar whether the tambaqui was reared free-swimming or in cages. Therefore, the prawns and the tambaqui are compatible for IMTA. Yield in IMTA was ∼0.6 t ha−1 prawns, 5 t ha−1 tambaqui in free-swimming and 3 t ha−1 in net-cages. In conclusion, the culture of Amazon river prawn and tambaqui in IMTA is technically feasible in the first grow-out phase of the tambaqui. This system is flexible and permits different management strategies according to the target markets for each species. • Prawns and tambaqui farmed in the same ponds, using recycled culture water showed high survival, grow rate and productivity. • About 600 kg/ha of prawn can be produced based only on the wastes of tambaqui diet and natural biota. • Feed conversion rate was improved in IMTA when compared to the monocultures. • The proposed IMTA systems allow farmers to diversify outputs and explore a wide range of markets. [ABSTRACT FROM AUTHOR]