I have set up tanks that crashed in week two and tanks that are still stable years later. The difference is almost never luck. This guide walks the pea puffer tank from empty glass to stable, livable water without the usual week-two crash.
Common mistakes
Adding fish during the first week, skipping the cycle, and skipping water tests are the big three. A 25% water change weekly, using this Apartment Tank Setup with Shrimp piece, prevents most problems before they start.
Beginner shortcuts
Keep it simple — a 10-gallon tank, a cycled filter, a heater, and live plants. Cycle 23 days, test the water, add a small hardy school, and do about a 25% weekly change.
What you need
- A 10-gallon tank and a stand rated for the weight (~40 kg when full).
- Filter rated for at least 40 L/h.
- Heater (if tropical): 54 W.
- Substrate: 2 cm deep.
- Live plants and a light on a 8-hour timer.
Step by step
- Rinse substrate, add it, and hardscape before filling.
- Fill slowly to avoid clouding; start the filter and heater.
- Cycle the tank — see this Cardinal Tetra Breeding piece — for 14 days until ammonia and nitrite read 0 ppm.
- Test water, then add a small group of hardy fish; build up slowly.
Next steps
Once stable, layer in more plants and a few peaceful tank mates. Keep a log of parameters; a tank you measure is a tank you can trust.
