Copper base medication will kill ich. It’s pretty strong and deadly to plants, algae,invertebrates and your biological bacteria. 
Some fish are sensitive to copper. Loaches and puffers comes to mind.
You will need to be sure after this has passed to watch your cycle. You may have another ammonia spike the bacteria recover
				
			Some fish are sensitive to copper. Loaches and puffers comes to mind.
You will need to be sure after this has passed to watch your cycle. You may have another ammonia spike the bacteria recover