I know otos can handle higher temps and malachite green/formalin. Also called Quick Cure. I don't know about the barbs though. I would google it to be sure.
My ich treatment consists of a large water change. Be sure to vacuum gravel really well. Slowly start raising temp to about 84-85. As much as the fish seem to be able to handle. If you have an HOB don't fill the tank all the way up so there's alot of surface disturbance (the higher temp means lower oxygen in water). I treat the water with Quick Cure. I've read this can be a harsh treatment so I use half the dose (like you would for tetras). It can also stain so keep that in mind. Every 3rd day I do a pwc. Keep treating until a few days AFTER all the white spots are gone.