Thanks Svelta. I'd feel absolutely terrible if in the future I accidentally sold brown gill to someone. This is the only way I know to make sure I only sell healthy shrimp. I just have to be able to live with myself. So no chance of selling brown gill now.
Shrimple minded- I uses the same sanitation as the CDC recommends for infectious diseases. 10% bleach solution. 1 cup bleach to 9 cups water. Dry well, rinse with freshwater, then dry again. Let sit for a day or two, then use as a new tank.
Any cholla, I throw out as I don't want that or other porous items to soak up and retain the bleach. I also go so far as to use new substrate.
And although most of us don't use these: Avoid using bleach on silk plants and brightly colored gravel or decorations, as it will fade them.