I use a syringe no needle needed just spray the aptasia till white then you know it is dead and any spores are also dead do this out of the tank. Make sure that you angle the rock so the water run off is the most direct so you don't kill off to much life. I have done this in a spot close to where I know that there was a mini bristle starfish and the starfish was fine. so if you are carfull you will be fine once the aptasia id dead you should give the area a rinse with salt water from the tank this cools it of hold the roch in the same manner so the cool water follows the same path as the hot water did. This limits the die off, also remove the dead aptasia. I have moved on to the use of peppermint shrimp they work better, I don't have to hunt for the little buggers any longer. Not that it was that much of a hassel but when I work out of town my wife does not go around looking for aptasia and killing it for me, now I have more free time to do what I want.

Bill