I’d be surprised if it’s ich if they aren’t eating, usually fish still have at least a small appetite with ich. Can you post pictures, I’m worried it could be velvet. What are you feeding? You might want to try adding garlic to their food, or maybe try some live foods like live brine might be successful. I’ve never been successful with live blackworms but I hear amazing things, those might be worth a shot, mixing their food with oyester feast has done the trick for me before. Id try a variety of different foods, getting them to eat is the most important thing. Also, how are you treating for ich/ what medication and or method are you using?