Red bugs are tiny crustacean parasites (1mm) that infest Acropora colonies. Visible as small yellow-orange specks on the coral surface. They cause polyp retraction and slow growth but rarely kill colonies outright.
Causative organism: Tegastes acroporanus
Severity: Moderate (cosmetic + slows growth)
Use a hand lens or jeweler's loupe. Red bugs are 1mm yellow-orange dots that move slowly across coral tissue. Differentiate from amphipods (faster, larger) and copepods (irregular movement).
Veterinary heartworm medication that kills red bugs in 6 hours. Crush 1 tablet (23mg or 11.5mg depending on size) and dissolve in tank water. Dose at 25mg per 10 gallons total system volume.
Interceptor kills shrimp, crabs, and other crustaceans. Remove cleaner shrimp, peppermint shrimp, hermits, and any ornamental crustaceans before dosing. Snails, fish, coral, and starfish are unaffected.
Activated carbon removes remaining medication. After 24 hours, return removed crustaceans to the display.
A single treatment usually clears the population but eggs hatching over 5-7 days can produce a second generation. Re-dose at day 7 if specks reappear on coral.
Red Bugs is preventable in 95%+ of cases by running a 4-6 week quarantine on every new fish before introduction. Read the quarantine protocol.