Where do I get good quality vannamei seed (PL) and how do I check it?

Seed quality decides your whole crop, so buy post larvae (PL) only from CAA approved and registered hatcheries that use certified Specific Pathogen Free (SPF) broodstock. Insist on a PCR test report showing the seed is free of major diseases like white spot, since stocking infected PL can wipe out the pond. Look for uniform size, active swimming and good gut content, and acclimatise the PL properly before release. Avoid cheap unbranded seed, which is a common reason for crop failure. Your state Fisheries department and the Coastal Aquaculture Authority can give you the list of approved hatcheries. Spending a little more on tested seed from a good hatchery is far cheaper than losing a whole crop.