🧭 10-Minute Rapid Search (in this order)

1. 🧱 Outside the tank (jumpers!)
   • Floor around/behind the stand, under furniture, on sump lids, inside the cabinet.
   • Inside the canopy/light hood, on center braces, along lid hinges.
   • 🚪 Quarantine pets (cat/dog) out of the room while searching—if the fish jumped, a pet may have found it first.
2. 🧊 Filters & back chambers (turn pumps off first; keep an airstone running)
   • HOB: box, intake strainer, impeller well.
   • AIO: rear chambers, under return pump.
   • Overflow/sump: weir teeth, downpipe, filter sock, skimmer section.
3. 🪵 Inside the tank (classic hideouts)
   • Under/behind driftwood, rock stacks, ornaments/caves.
   • In dense plants, behind backgrounds, inside sponge filters/PVC elbows.
   • Burrowers: look for fresh mounds or pits.
4. 🔦 Search smart with light
   • Room dark → small flashlight from above; watch for gill movement.
   • 🌙 Red light at night for shy/nocturnal species.

🧬 Species clues (where they “vanish”)

• Freshwater: kuhli/loaches (burrow), plecos/catfish (tight cracks), bettas (leaf naps/lid gaps), cichlids (caves).
• Marine/Brackish: wrasses (bury), gobies/jawfish (burrows), firefish (jumpers), blennies (holes/tubes), eel-likes (overflow/plumbing).

🛟 If you find the fish (rescue)

• ⚠️ Stuck in HOB/overflow/sock: keep it wet, power off, lift gently with a wet hand/net.
• 🌬️ Fast breathing: move to high-O₂ water (main/QT with airstone), lights low.
• 🩹 Scrapes/tears: pristine water; consider brief methylene blue bath (freshwater) in a separate, aerated container.

🧪 If you still can’t find it (next 24 hours)

• 🧪 Test ammonia & nitrite. A rise suggests a hidden death—start 30–50% water changes and run carbon.
• 👀 Watch the clean-up crew (snails/shrimp/hermits/bristleworms); they cluster where a body is.
• 🪤 Reality check: In active tanks, a dead fish can be reduced to bones in a few hours by tankmates/scavengers—sometimes you won’t see a body at all and it truly seems to “vanish.”
• 🐾 Pets: If you have a cat or dog, a jumper can be carried off/eaten before you notice. Keep lids tight and doors shut to prevent this scenario.
• 🔎 Deep check: Lift decor carefully (brace rockwork), inspect under/behind stacks, check hoses and return lines.
• 🎥 Set a night cam or check 2–3 hours after lights out with a red flashlight.

🛡️ Prevent the next disappearance

• 🧢 Tight lids & gap covers: mesh over overflow teeth, block cord notches/gaps.
• 🧲 Intake guards: fine sponge prefilters on intakes; strainers on overflows.
• 🏚️ More hides: extra caves/plant thickets reduce roaming/jumping from stress.
• 🤝 Tankmate audit: remove bullies; shy fish do better in groups.
• 🌡️ Stability: steady temp, pH, and flow; stressed fish hide/jump.
• 🍽️ Feeding routine: same time daily—“missing” fish often reappear at meals.
• 🚪 Pet control: keep doors shut; supervise when lids are open.

📝 Quick checklist (print me)

• 🔌 Pause pumps safely → keep an airstone on.
• 🔦 Scan floor/hood/brace → filters/overflow/sock → inside tank (wood/rocks/plants/sponge).
• 🐾 Consider pets as a cause for disappearance.
• 🪣 If found stuck: keep wet, gentle lift, low light, high O₂.
• 🧪 If not found: NH₃/NO₂ tests, water changes, carbon; re-scan at night.
• 🛡️ Add lids/mesh/guards, more hides, review stocking & stress.