Most setup advice skips the part that actually prevents problems: getting the foundation right before fish go in. This guide walks the EI fertilizer method from empty glass to stable, livable water without the usual week-two crash.

What you need

Step by step

  1. Rinse substrate, add it, and hardscape before filling.
  2. Fill slowly to avoid clouding; start the filter and heater.
  3. Cycle the tank — see our lymphocystis: the 'cauliflower' wart virus in fish guide — for 28 days until ammonia and nitrite read 0 ppm.
  4. Test water, then add a small group of hardy fish; build up slowly.

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 our endler's livebearer care: pocket-sized colour guide, prevents most problems before they start.

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.