thanks for diigging out that info. If the whole grow-out period takes only 16 weeks (4 cycles per year per tank) and the first stage is about 6 weeks for 110/kg size, the remaining 3 stages take only about 8 weeks together. So the prawn can only grow to a certain size (maybe 20-60 per kg) before being sold out. Your assumption of 100/kg seems reasonable although it may turn out to be less.
I think the reason they use the Giant species is more because of their ability to grow quickly in the first 16 weeks (for more efficient marketing) than because of their final size haha.
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