Brackish tank: step-by-step setup

5 steps from choosing the spot to adding the first fish.

1. Choose the tank

   A bigger tank is easier to keep stable. 60–100 L for a beginner. Custom glass: up to 30 cm high 5 mm, 40–45 cm 6 mm, 50–60 cm 8–10 mm. Aquarium silicone only, cure 48 h and leak-test two days.

2. Low salinity

   Marine salt (not table salt) to 1.005–1.015 by species. Monos and scats move up to full marine as they grow.

3. Cycle the tank (the key step)

   Fill with dechlorinated water, run filter and heater, add an ammonia source (a pinch of food daily or 2 ppm ammonia) plus bottled bacteria. Test every two days: ammonia rises, then nitrite, then nitrate. Ready when ammonia and nitrite read zero three times in a row and nitrate shows (2–6 weeks). Log the tests and Zajel shows the stage.

4. Fish

   Green spotted puffer (alone), archers, monos, scats, bumblebee gobies, mollies. Puffers need snails to trim their teeth.

5. Maintenance routine

   Feed once or twice a day what is eaten in 2–3 min, one fast day a week. Change 20–30% weekly with matched, treated water. Rinse filter sponges in old tank water, never tap water. Test weekly. Zajel reminds you.