I was able to make it work, I had a large (4") Maroon clown and I purchased a Small (Maybe 2") Maroon Gold stripe. I was worried at first, but the blue devil damsel went after it first, the large clown came out and nailed the damsel. After that the clowns were the best of friends, I think they are even trying to mate.
The damsel won't even look at the clowns now.
If this is going into your 180g, I would think it would work. It worked in my 140G. Good luck!
<img src="graemlins//angel.gif" border="0" alt="[angel]" />