power head should work, just make sure its not gonna head towards the filter. had one get stuck in there, got him out, but not without some war wounds, doin fine though. i usually pick them up with my hands fr the tank, havent been stung yet.
notice u have galaxy coral! nice. my ricordia decided to suck in one of its tenticles the other day, no bueno for the ricordia. after 2 days starting to look normal again.