Freshwater community (beginner): step-by-step setup
7 steps from choosing the spot to adding the first fish.
Choose the spot
Away from direct sun, AC and doors, near a socket, on a floor that takes the weight (about 1 kg per litre + 20%). The stand must be perfectly level.
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.
Equipment (sized from the litres)
A filter turning the water 4–6 times an hour, a heater of about 1 W per litre, LED light 6–8 h on a timer, air pump and stone, thermometer, dechlorinator, and a bucket and siphon for the tank only. See the equipment calculator below.
Substrate and decor
Well-rinsed gravel or sand 3–5 cm, inert stones (river, slate, lava) and boiled or soaked wood. Easy plants: anubias, java fern, crypts, vallisneria, java moss. No limestone or painted decor.
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.
Add fish slowly
Start with 3–6 hardy fish, add the rest after two weeks. Check compatibility in the library first. Quarantine new fish 2–4 weeks if you can. Acclimate: float the bag 15 min, add tank water every 5 min, net the fish in without the bag water.
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.