I got a buddy whose got 4 tangs (purple, sailfin, naso, and yellow) and he's got it in a 125g. they're doing ok, and they've gotten used to each other, so they don't fight. I'm going to put them in my tank (180g). but those are not my favorite tangs..... I really want either an achilles or a sohol tang. my question is can I put those in now, and then add a sohol or add an achilles later? most likely I'll want a sohol. thanks for any input.