Disclaimer: Based on the preventive measures outlined in the scientific review “Infectious diseases in aquarium ornamental pet fish.”
You go to the shop. You buy a beautiful new Neon Tetra. You bring it home, float the bag, and release it into your main tank.
Three days later, your new Tetra has white spots. Five days later, your old Angelfish (which you have had for 2 years) is dead.
This is the “Russian Roulette” of fishkeeping.
According to veterinary science, the stress of transport lowers a fish’s immunity, making them “shed” bacteria and viruses right after you buy them.
The only way to stop this is Quarantine (QT). It sounds expensive, but in Malaysia, you can set one up for less than RM30.
1. What the Science Says
The research paper recommends a quarantine period of 15 to 90 days.
- For Commercial Farms: 90 days is standard.
- For Hobbyists: I recommend the “15-Day Rule.”
- Why 15 Days? Most virulent diseases (like Ich, Velvet, or Columnaris) have life cycles that will show symptoms within 2 weeks. If the fish is still healthy after 15 days, the risk drops significantly.
2. The RM30 Setup (The “Toyogo” Box)
You do not need a glass aquarium for quarantine. In fact, a plastic tub is better because it is opaque (less stress) and easy to store.
The Shopping List:
- Plastic Storage Box: Any “Toyogo” style container (10L – 20L). Cost: RM10.
- Sponge Filter + Air Pump: Cheap and effective biological filtration. Cost: RM15.
- Anti-Chlorine: Essential. Cost: RM5.
- No Gravel: Keep the bottom bare. This lets you see poop (to check for worms) and clean it easily.
3. The Protocol: What to Do
Days 1-3: Observation
Put the new fish in the tub. Do not feed them on Day 1. Just let them rest. Watch them closely. Are they breathing fast? Are they scratching?
Days 4-7: De-worming (Optional but Recommended)
Since Malaysian farm fish often have internal parasites (as we discussed in the Guppy post), I often feed them Medicated Food during this week just to be safe.
Days 8-14: The “Stress Test”
Feed them normally. Do water changes. If they are eating aggressively and swimming actively with no spots or sores by Day 14, they are likely safe.
Day 15: Graduation
Move them to the main tank.
4. What if they get sick?
If you see White Spot or Rot during quarantine—Good News!
You caught it in the tub. You can treat the cheap tub with medicine without staining your beautiful main tank or killing your expensive plants.
Once treated and cured, restart the 15-day clock.
5. “But I only bought one fish…”
It doesn’t matter.
One RM2 fish carrying “Fish TB” or “Velvet” can wipe out a RM2,000 planted tank setup. The cost of the quarantine box is nothing compared to the cost of replacing your entire ecosystem.
Quarantine is not just for professionals. It is for anyone who loves their fish.
Buy a plastic box. Keep it in the storeroom. The next time you buy fish, use it. Your future self (and your old fish) will thank you.
