Territorial Tangs

Hey guys I have a quick question. I have a 125 gal reef aquarium and want to add a powder blue and or a Achilles Tang. My dilemma is that I already have two yellow tangs and they are pretty territorial and dominate. I have attempted to add a sailfin tang before and they bothered it until it was stressed to the max. It got ich and died within two days. My question is can I remove the two yellow tangs for a week or two until the new additions are acclimated and comfortable then add them back. I would change up the aqua scape around also to attempt to tame some of the territorial behavior. Any help and or suggestions would be great.