[steve the plumb]

I had 6 tangs in my 150.It was fine but my tank had a lot of live rock.I do think it was a lot of tangs for a 150.They did fight when it came to feeding time but they were all well fed.At least you are going to a longer tank that will allow more swimming space.You also have the advantage of giving them a brand new home so they will establish there territory but they have a lot more space to do so.