I'd demand a refund from your hatchery at a minimum, or threaten to litigate to drain, seine, nuke, and start over with new stocking. A hatchery selling contaminated stock should be brought to justice and should NOT be in business. If you want an invoice from a pond and fishery management professional I might know someone who would help. This is complete BS - don't bend over.
Per Scott I would not abandon your dreams of a cool water species fishery - they're my speciality and are a true joy to manage. I manage SMB/WE/HSB/YP fisheries with BG present and their [BG] population management is a chore. I think a restart is a good idea, but only if the hatchery is going to be held responsible. If you want help thinking through this reach out anytime. Whatever you do don't stock LMB and give up! We can still make it.
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