🔍 Find an aquatic vet
- Search the WAVMA (World Aquatic Veterinary Medical Association) directory — or search "aquatic / exotics vet near me".
- Call ahead: "Do you treat marine fish?" Few vets do — find and save one now, while things are calm.
- Ask the exam fee when you call — knowing the cost up front removes the money-panic in a crisis.
📇 Fill this in now
🚨 Is this an emergency now?
Quarantine and get help promptly if you notice any of these:
- White spots (ich) — expect and watch for it; quarantine and treat immediately, as this species is extremely prone.
- Rapid breathing, flashing, or blotchy stress colouration — parasites or water quality; act fast.
- Not eating, thinning, or being bullied/bullying — stress; a hungry or stressed powder blue declines quickly.
🚗 On the way / while you wait
✅ Do
- Test your water NOW — salinity, ammonia, nitrite, nitrate, alkalinity and temperature — and correct anything obviously off.
- Move the fish to a hospital / quarantine tank if you have one.
- Keep it in its own stable tank water.
- Keep the tank calm and dim.
⛔ Don't
- Don't dose the display tank with OTC or shop “cures” blindly — copper and many meds are harmful to inverts and corals, and they mask the real cause.
- Don't make a big, sudden parameter swing.
- Don't add anything you can't explain the reason for.
🎒 What to bring
- A recent, full water test — salinity, alkalinity, nitrate, temperature (and ammonia/nitrite/pH if you have them).
- Photos plus a short video of what you’re seeing — it may not show it in the clinic.
- A note of your system and how you feed.
- Only if advised: the animal itself, in its own tank water.
🗣️ What to tell the vet / expert
- Adult size
- Up to ~9 in.
- Minimum tank
- 125+ gallons with lots of open swimming length and strong flow/oxygenation.
- Temperature
- 75–82°F (24–28°C).
- pH
- 8.1–8.4.
- Specific gravity
- 1.023–1.026 (reef-standard ≈35 ppt).
- Diet
- Herbivore — needs constant grazing: lots of nori/dried algae and herbivore foods, plus tank algae. A hungry powder blue is a stressed, ich-prone powder blue.
- Temperament
- Territorial and often aggressive — especially toward other tangs — and it can bully tankmates. One tang per tank; add it last. Scalpel-sharp tail spine.
- Reef-safe
- Yes with corals — it grazes algae, not coral — but its temperament and disease-proneness make it a challenging tankmate, not a peaceful one.
- Natural range
- Indian Ocean.
⚕️ Most marine illness starts with water quality or acclimation, not infection — bring a full set of parameters (salinity, alkalinity, nitrate, temperature). Marine-fish medicine is specialised and few vets treat fish, so call ahead. Copper and many OTC 'cures' are toxic to invertebrates and corals — never dose them in a reef display; treat a sick fish in a separate quarantine/hospital tank, and tell the vet exactly what you've already added.
❓ Questions to ask
- Do you treat marine fish?
- What are the likely causes — and could my water or acclimation be the cause?
- What is the treatment plan, the likely cost, and what should I watch for?
- How do I prevent this happening again?