I have been treating my 3 mollies and guppy for ich. When I got home tonight, 1 mollie and the guppy were dead. Also the pleco is not looking good. He looks very pale.
What are you using as ich medication? Did you raise the tank to around 82 degrees F. Also did you add salt you help the life process of the ich parasite go faster?? Just some ideas.
I agree, increase your temp to 82-84F, use ich medecine and salt combination, and increase aeration for your fish. Water changes must happen more often too to remove more of the disease.