Hey ReefNut, I think it is fairly common for clowns to behave the way you described. Staying behind powerheads, hovering in the corners, etc, when first introduced into a new tank. I have read other posts where someone was asking why their new clown was acting odd, scared, or otherwise just uncomfortable. Additionally, we just moved a female clown to a different tank yesterday and she is doing that same thing. She came out of a tank with high flow and went into a tank with low flow and so far has been hanging out behind a powerhead. I understand why that coupled with their "unique" swimming style would make it appear they have a difficult time dealing with flow. They look like they are constantly swimming against a current when even in a very calm tank.