How to set up your first freshwater aquarium
AquaLog guide · Published
In short: Choose a tank of at least 60 litres, set it up with a filter, heater and dechlorinated water, and cycle it for four to eight weeks before adding fish. Then add a few hardy, compatible fish at a time.
What size tank should a beginner get?
Bigger is easier. A larger volume of water dilutes mistakes, so temperature and water quality change more slowly. A 60–100 litre tank is a good first aquarium; small tanks and bowls go wrong faster. Water weighs about 1 kg per litre, so put the tank on a stand made for it, on a level floor, away from direct sunlight (which feeds algae) and away from radiators, draughts and doors.
What equipment do you need?
- A filter rated for your tank's volume. It houses the bacteria that keep the water safe.
- A heater and a thermometer for tropical fish. About 1 watt per litre is a common rule of thumb.
- A light and a lid. Many fish jump.
- Substrate (gravel or sand) and decoration: rocks, wood, live plants.
- Dechlorinator for every bit of tap water you add.
- A test kit for ammonia, nitrite, nitrate and pH.
- A gravel vacuum and a bucket used only for the aquarium.
How do you set it up?
- Rinse the substrate until the water runs clear, and spread it in the tank.
- Place rocks, wood and plants. Live plants help from day one.
- Fill slowly with dechlorinated water, pouring onto a plate or bag so the substrate stays put.
- Start the filter and heater, and check the temperature after a day.
- Cycle the tank before adding any fish. See how to cycle an aquarium.
What are good first fish?
Pick hardy, peaceful species that suit your water. Our care guide rates these as beginner fish:
- Zebra danio: active, tough, keep 6 or more.
- Platy: colourful livebearer that likes harder water.
- Cherry barb: peaceful barb, keep 6 or more.
- Bronze corydoras: bottom-dwelling catfish, keep 6 or more on soft sand or smooth gravel.
- Harlequin rasbora: calm schooling fish, keep 8 or more.
Check each species' adult size, group size and water range before you buy, and make sure they suit each other. See how to choose compatible tank mates.
How fast can you add fish?
Slowly. Add a few fish, wait one to two weeks, and test ammonia and nitrite. If both read zero, add the next few. The filter bacteria grow to match the waste they receive, so a gradual increase gives them time to keep up.
What should the first few weeks look like?
- Feed small amounts once or twice a day: only what the fish finish in a couple of minutes.
- Change 10–25% of the water every week. See how often to change aquarium water.
- Test often and watch the fish every day.
AquaLog keeps the whole record for you: each fish when it arrives, every water change and test, and reminders for what's due. Set up your first tank in AquaLog.