That stuff is nasty and hard to get rid off.
Since you are only using a 10 gal with a simple filter and a powerhead I would sudgest puling everything out of the tank. Then you clean your tank, filter, powerhead with boiling water or some crazy harsh chemical (bleach). After you did that you will have eliminated about 90% of it. The last step would be to somehow clean your corral and the rock (plugs) they are on. Maybe someone on here can tell you how to eliminate it from those parts.
Like Steve above stated oxygenating the water will only help so after the whole cleaning you could add another small powerhead just below the water line or witha airline in the intake to blast the tank with bubbles...
Good luck,
BK