Prevention
The best method of avoiding an infection is to quarantine every new frag coming into your tank. That will give you a chance to examine it for a while before introducing it into the display tank. I have also heard of using Tropic Marin Coral Cure or iodine as a dip, which also helps prevent Acropora eating flatworms (AEFW) and nudibranches - I think. (Be warned, many people do not consider the dips to be effective for all these parasites or their eggs.) Some people will also do a treatment with "Interceptor" before placing a coral into their system.
Treatment
Once you find an infection, it becomes necessary to treat the tank or all the acros in a QT tank. Since acropora species are the only corals affected, you can remove all the acros to a small QT tank and treat them there instead of treating the entire display tank. The drug of choice is a dog and cat heartworm medication called Interceptor. The active ingredient "Milbemycin" is a very effective antibiotic that will specifically target crustaceans including the red bugs. Prior to treating, you should remove all crabs and shrimps that you want to save. See the following link for detailed instructions on how to use Interceptor: http://www.reefs.org/phpBB2/viewtopic.php?t=45859.
Dosing
Interceptor comes in several different doses, the one that is used is the pill for large dogs (50-100 pounds). Place the pill in a plastic container and crush it into a powder with the back of a spoon. If you have a sensitive scale, the dose is 25 mg of powder per 10 gallons. This is an estimate and it's not common to have a scale that sensitive. The entire pill weighs 1000 mg so some people just estimate - for example, a 100 gallon system would require 250 mg of powder, or 1/4 of a pill. The exact dose doesn't seem to be that important. In a conversation with TDWyatt, he explained that acroporas seem to be free of any side effects from the Milbemycin (but don't go dosing at 100X the recommended!).
Before dosing your tank, be sure to remove any crabs or shrimps that you want to save. Although some people have not lost any desirable crustaceans from a treatment, it's still a good idea.
Duration
The orginal treatment was supposed to last for 6 hours and then a 25% water change was done and carbon was added to the system. 3 total treatments were done one week apart. There is newer information about red bugs now. It seems that they have a 5 day life cycle and a 3 week treatment cycle may not be necessary.
Eric Borneman (don’t laugh) has some observations about treating red bugs and recommends a much longer treatment period - 12-24 hours instead of just 6. His observation is that longer treatment times and not higher doses are more effective in eliminating red bugs. (http://www.ericborneman.com/Tegastes...Treatment.html) I have treated my acroporas for 24 hours without any negative results. If you were to use a QT tank for treatment, keep the acroporas out of your display for at least 5 days (to allow all the existing red bugs to die from the lack of a host).
Storage
TDWyatt recommends keeping the unused powder in an opaque medicine bottle (clearly labelled) in the fridge. That should keep it good for a while.
Good luck everyone, and I hope you never get the dreaded red bugs
