The FAO (2022c) describes a system in which 4,500 hatchling carp are concurrently stocked to feed each mandarin fish. If this is typical then mandarin farming overall consumes an estimated 3,000 billion feed fishes, i.e. 3.0 × 1012, based on an estimated 674 million mandarin fish (Table 3).
According to field practice, live foods should be at a density of 3 800–4 500 fish per m2. Moreover, the size of the live food should be well controlled to keep pace with the growth rate of the cultured fish. In order to provide an appropriate quantity of live food, provision procedures are suggested as: 1 to 4 days after pond fertilization, silver carp and bighead carp hatchlings are stocked as live foods at 1 500 per m2; one week later, the same quantity is again stocked; and again an additional week later, stocking of the same number is performed. The third stocking should be accompanied by the stocking of mandarin fish of size 3–4 cm at an average rate of 1 fish per m2.
So 1 mandarin fish per m2 vs 3 800–4 500 feed fish per m2?
Mood et al., 2023 had an earlier estimate:
From the FAO source (archived):
So 1 mandarin fish per m2 vs 3 800–4 500 feed fish per m2?