I currently have two clownfish in quarantine (They're not showing any problems anymore and should be safe to put back in the 44gal in a couple days), but the female loves to pick on the male... The solution? Let the male hide in a breeder net!
Pretty soon, the clownfish has learned that the breeder net keeps it from getting pestered, and now willingly goes into it whenever I place it in the water!
Usually I've hand-lifted him from the water and placed him in the breeder net, but lowered the net into the water to let him swim out during feeding times...
Now, instead of lifting him out to put him in the net, I just let him swim in and out of the net as he pleases.
YouTube - Clownfish Rescue