Look for white fuzzy spots or patches on your fish. It may also look like white strings coming off of their bodies. Usually the newest fish in your tank are the most likely to contract ich.
A fish with ick will have small white spots all over its body. It will also behave abnormally. This abnormal behavior would include a loss of appetite and swimming into objects in the tank.
It will look like white air bubbles all over the fish. They will act sick also like they are sick lethargic and not moving as much as they should either. You get the medication and apply it to the water and it should start clearing up within a few treatments.
