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.
Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.
Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.
Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.
Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.
Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.
How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.
What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.
How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.
Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.
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