I grow the Malaysian freshwater prawn, which matches the pictures above without any trouble. You do have to get creative with space/territory though. You buy them post larvae stage, and grow out. Post larvae to table is 4 months.
And the $ value of these far exceeds the marbles.
There's no mudvein on these, so no deveining needed. Straight from grow out, rinse and grille. At maturity, 7-8 = 1 lb. 1 lb sells for $20. Just an FYI.
At first I left this blank...but now I believe: "It's better to keep your mouth closed, and have the world think your a fool, than open it and confirm it."