99% of freshwater ich treatments will kill your invertebrates.. Anything that contains copper, malachite green or formalin... Put your fish into a qt tank by himself and treat with Rid Ich+.. Treat for 14 days.. Wait an additional 2 weeks then reintroduce him back into your display tank.. The life cycle for ich is approx 10 days.. You want to make sure you catch any that are in mid cycle.. The meds will not affect them in the cyst stage, they have to be free swimming...