Feeding or not feeding while being on meds depends on what they are being treated for and what they are being treated with. Some meds are harder on nitrifying bacteria than others and in that case feeding should be kept to a minimum to avoid too much waste being produced by the fish and causing an ammonia build up. Other conditions you would feed during or feed very lightly may be if the fish has a grastric infection or IP's. Some meds put fish off there feed and they don't eat while being treated anyway. As far as ich itself goes you can feed during treatment but feed lightly, most ich meds don't impact the BB that much. What are you treating with?
