Acropora Red Bugs
Tegastes acroporanus a species of copepod (crustacean)
Red bugs are small flea-like beasts that can infest smooth-skinned acropora sp. Red bugs do not always kill the coral on which they live. But they can affect growth rate and overall health. The crustacean feeds off of the slime and waste products produced by the Acroporas.
Description
Very tiny (approx1/2mm) crustacean; yellow in color with a red dot, approximately 1/2 mm in length.
Symptoms & Signs
If you have an established colony of Acropora sp. that begins losing coloration and stops showing normal polyp extension, take a closer look at the tissue of the coral for any small yellowish/red specks. It is oftentimes easiest to distinguish these pests on the shadowed underside of a branch. An infected colony of Acropora will typically show poor or no polyp extension, and will slowly lose coloration over time. As a result of this infestation, it has been found that the growth rate of the colony is seriously affected, and may even result in death to the coral itself.
It is not clear why these bugs prefer certain species of Acropora over others, nor is it clear why they are not found on other SPS corals such as Montipora, Pocillopora, or Seriatopora.
Solutions
The best way to fight this pest is by prevention. If you have recently purchased an acropora and used your quarantine tank you will lessen your chances of infecting your entire display tank. While in quarantine we recommend using RPS All Out Dip to rid your coral of these pests.
Natural Predator
Dragonface Pipefish (Corythoichthys haematopterus) - will anchor themselves on the branches of Acropora and begin to feed on tiny crustaceans as well as red bugs. The Dragonface Pipefish is among the hardiest pipefish, but is difficult to keep due to its unusual feeding requirements. It normally prefers to eat only live copepods in a mature reef aquarium with plenty of live rock or macroalgae. As with any addition to your tank please read up on the care and compatibility before introducing the pipefish into your tank.
Chemical Solution
Interceptor Treatment - We at RPS do not recommend this as it will affect your entire tanks parameters and will kill other crustaceans such as crabs, snails, starfish etc that you may be beneficial to your tank. Also, because interceptor is a dog heart worming medication; there are only suggested instructions given by those who have tried this method some with success. This should be used as a last resort method and with EXTREME caution. (Some out there suggest removing and treating the corals separately. But remember, red bugs are free swimmers so if you remove the coral there is still a high probability that a few bugs have swam away and will reinfect your coral once reintroduced.)
Sources
http://aquariumcoraldiseases.weebly.com/red-bugs.html
http://en.wikipedia.org/wiki/File:AcroBugs.jpg
http://www.advancedaquarist.com/2003/6/aafeature