best way to treat ich

[fishguy29]

Hi there. I have 2 clowns and a regal tang. The clowns i have had for 3 weeks with no issues and the tang 1.5 weeks. The tang showed signs of ich alittle then went away and now its pretty bad. One of the clowns is now sticking his mouth out of the top as if he is trying to get air. I'm adding an airstone to try and add more oxygen and the top is open now. I'm curious should i take the 2 clowns and regal tang out and qt them? i just setup the qt tank and didn't want to add more stress but what do you all think is my best option.