[ConservativeMind]

Thank you both for the heads-up, but there seems no way to make this practical, at this time.

Cysteine can't be added, then separated out, retaining the mercury, without their sequestering bag to enclose the resulting compound.

[minnesota_bound]

Eat Walleye instead.
Sunfish & Crappie are good too.
Northern Pike has too many bones.