Every new fishkeeper has a long list of questions, and having those aquarium beginner questions answered by experienced hobbyists saves time, money and livestock. At Gensou Aquascaping at 5 Everton Park, we hear the same queries every week from customers setting up their first tanks. Here are the 20 most common questions with straightforward, practical answers.

1. How Long Should I Cycle My Tank Before Adding Fish?

Allow four to six weeks for the nitrogen cycle to complete. Test for ammonia and nitrite — both must read zero consistently before adding livestock. Seeding with mature filter media from an established tank can reduce this period to two to three weeks.

2. How Often Should I Change the Water?

Perform a 25 to 30 per cent water change once a week. This removes accumulated waste and replenishes minerals. Shrimp-only tanks may benefit from smaller changes of 10 to 20 per cent to minimise parameter swings.

3. Do I Need a Heater in Singapore?

Most tropical fish thrive at Singapore’s ambient room temperature of 27 to 30 degrees Celsius, so a heater is usually unnecessary. A cooling fan is more useful — it lowers water temperature by two to four degrees through evaporation, which benefits temperature-sensitive species and plants.

4. How Many Fish Can My Tank Hold?

A rough guideline is one centimetre of adult fish length per two litres of water, but this varies by species. Active swimmers need more space than sedentary bottom-dwellers. Research each species’ requirements individually rather than relying on a single formula.

5. Why Is My Water Cloudy?

Cloudy water in a new tank is usually a bacterial bloom, which resolves on its own within a week. Green cloudiness indicates an algae bloom, typically caused by excess light or nutrients. Reduce the photoperiod and perform partial water changes to address it.

6. Can I Use Tap Water?

Yes, but always treat it with a water conditioner to neutralise chlorine and chloramine. Singapore’s PUB water is safe for most tropical fish once dechlorinated. For sensitive species like Caridina shrimp, many hobbyists prefer reverse osmosis water remineralised to specific parameters.

7. How Long Should My Lights Be On?

Seven to eight hours per day is ideal for planted tanks. More than eight hours increases algae risk without significant benefit to plants. Use a timer to maintain a consistent schedule.

8. Do I Need CO2 for Plants?

Many aquarium plants grow well without CO2 injection — Java Fern, Anubias, Cryptocorynes and mosses are excellent low-tech choices. CO2 injection benefits demanding species and accelerates growth across the board, but it is not a requirement for a beautiful planted tank.

9. Why Are My Fish Gasping at the Surface?

This indicates low dissolved oxygen. Increase surface agitation by adjusting your filter outflow or adding an airstone. Check the water temperature — warmer water holds less oxygen. In Singapore’s climate, adequate surface movement is essential.

10. How Often Should I Feed My Fish?

Once or twice daily, offering only what they can consume within two to three minutes. Overfeeding is one of the most common beginner mistakes and leads to poor water quality, algae and health problems.

11. Can I Mix Different Fish Species?

Yes, provided you research compatibility. Combine peaceful species of similar size and temperament. Avoid mixing aggressive fish with timid species, and never house predators with fish small enough to be eaten.

12. What Is the Nitrogen Cycle?

Beneficial bacteria convert toxic ammonia (from fish waste) into nitrite, then into less harmful nitrate. This process must be established before adding fish. Nitrate is removed through water changes and plant uptake.

13. Why Are My Plants Melting?

Plants often melt when transitioning from emersed (above water) to submersed (underwater) growth. This is normal. Remove dead leaves and wait — new submersed growth should appear within two weeks. Ensure adequate lighting and nutrients to support recovery.

14. Do I Need a Test Kit?

Absolutely. A liquid test kit for ammonia, nitrite, nitrate and pH is essential for monitoring your tank’s health, especially during cycling and when troubleshooting problems. GH and KH kits are important additions for shrimp keepers.

15. How Do I Get Rid of Algae?

Reduce the photoperiod, balance nutrients, ensure stable CO2 if injecting, and introduce algae-eating livestock like Amano shrimp and Otocinclus. Manual removal and consistent maintenance prevent minor algae from becoming a major problem.

16. Can I Keep Fish in a Bowl?

Bowls are unsuitable for fish. They lack filtration, have poor oxygen exchange and offer insufficient swimming space. Even Betta fish, which are commonly marketed for bowls, thrive far better in a filtered tank of at least 10 litres.

17. How Do I Know If My Fish Are Sick?

Common signs include white spots, clamped fins, loss of colour, lethargy, refusal to eat, rapid breathing and unusual swimming patterns. Isolate sick fish in a quarantine tank if possible and research the specific symptoms to identify the disease.

18. Is It Normal for Fish to Hide?

New fish often hide for the first few days as they adjust to unfamiliar surroundings. Provide adequate hiding spots — plants, caves and driftwood — to help them feel secure. If hiding persists beyond a week, check water parameters and look for bullying by tank mates.

19. Can I Go on Holiday Without Feeding My Fish?

Healthy adult fish can safely go without food for up to a week. For longer absences, use an automatic feeder set to dispense small portions once daily. Avoid “vacation feeder” blocks, which often cloud the water and degrade water quality.

20. Where Should I Buy My Fish in Singapore?

Choose a reputable local fish shop that maintains clean tanks and healthy livestock. Observe the shop’s tanks — clear water, active fish and minimal dead specimens indicate good husbandry. Visit Gensou Aquascaping at Everton Park for quality livestock, plants and honest beginner advice from experienced aquarists.

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20 Most Common Aquarium Beginner Questions Answered