Watch this step by step how-to video showing you probably the easiest way to kill Acropora eating Red Bugs, or Tegastes acroporanus, if you can get the corals out of the tank. If you can't get them out of the tank then you'll need to use Interceptor instead, which I'll be making a video for at some point as well. The directions are as follows:
2 cups tank water
0.5 ml Bayer Advanced Complete Insect Killer
WEAR GLOVES THE WHOLE TIME, THIS STUFF IS POISONOUS!
Dip the coral for 15 minutes, shaking the coral every 4-5 minutes to remove the dead red bugs.
Afterwards transfer the coral to another container of tank water for 10-15 minutes to remove the leftover insecticide that's left on or in the coral and rock. If you put the coral back into the tank it was in you're going to get red bugs again, so you'll need to quarantine the coral or keep a really close eye on it and keep dipping once a week for a little while until they finally go away.