Wrasse behavior

[Amy]

I have a longfin fairy wrasse that's been acting weird for 3 weeks now. He's always swimming upside down or upwards tail touching the sand bed  and rests on its back all crooked in a 90 degree angle. He's breathing normally and he always comes out to eat when I give them food.
At first I thought it was just stress, but after 3 weeks? I only have one ocellaris and a tailspot blenny for fish, and neither of them are being aggressive with him, they're never near him actually.
He also rubs his back a lot of the liverock and sand, and it looks like he's always having difficulty swimming, even in low current areas.
He Really looks like a dying epileptic fish all the time, I just don't know what to think anymore...

Is it normal? Is it just stress or is there something really wrong with him?

He's still all colorful and he doesn't seem injured or anything.  A week and a half ago, I thought he was dead, he was lying on his side and I caught him with the net to get a closer look. He wasn't moving, so I grabbed him with my hand to take him out of the water. As soon as I got close to the surface, he freaked out and jumped out of my hand and went back on the sandbed to rest on its back, and started to breath normally again... 
It scared the hell out of me lol, I wasn't expecting this at all!

Have you ever observed this behavior before?  I'm used to freshwater fish, and when a fish does that, it usually gets eaten or dies the day after... But he seems pretty eager to live another 5 years lol

[kole18]

That's normal for fairy wrasse to swim like that, it will also flash its fin like showing own natural color as long as its eating well & active your fish is gonna be ok.

[Hookup]

I believe it could be parasites, such as gill flukes

He sounds stressed...  Scratching can mean parasites, but some scratching is normal...


The normal breathing is deceiving though...  I've not owned that particular species...  Maybe it is normal...  Just sounds like an issue...  If any of my fish did that, I'd try to fish-trap them out and QT them...