The harlequin would definitely make the Linkia into a fews days worth of meals! I really like the Harlequins, but I to know that they would eat any starfish you have in your tank.
We would use a small brine shrimp net, and run it up the glass. They would come right off the glass and fall into the net. We had a guy a town over from us with a Harlequin. We would just call him when we had a bunch.