She said that the home office (its a local chain pet store) warned them that copper could be the cause of the shrimp dying because they also for some reason have copper in their water even before adding any to the tanks. She said they use the copper meds for
ICH and algae outbreaks... this place is notorious around here for having low quality sickly fish anyway (not to mention ignorant employees) so I never get my fish there, just food and supplements.
EDIT : Oh and SDS, they definitely have further issues lol... their plant tanks are horrid, they never clean them... theres about 1/2 to 1 inch of dead plant leaves and mulm on the bottom of the plant tanks... all of the plants are infested with snails... all of the plants are covered in algae and that weird 'rust' stuff... they actually put severely injured or seriously sick fish in the plant tanks to let them heal, thats really great for people who buy plants to spread infection and disease around isnt it!