Best Fish for HDB Aquariums: Size, Noise and Weight Considerations

HDB-Specific Considerations

Keeping an aquarium in an HDB flat is enormously popular in Singapore, but it comes with practical constraints that landed property owners do not face. Floor loading limits, noise from equipment that travels through shared walls and floors, limited space in compact layouts, and electrical capacity all need to be factored into your planning.

The good news is that with thoughtful planning, an HDB flat can accommodate a beautiful, thriving aquarium. Thousands of Singaporean hobbyists maintain stunning tanks in their flats — from simple betta setups on study desks to impressive 4-foot planted aquascapes in living rooms. The key is choosing the right tank size, equipment, and fish species for your specific situation.

Recommended Tank Sizes for HDB Flats

The most important limiting factor for HDB aquariums is weight. HDB flats are designed with a live load capacity of approximately 150 kg per square metre for residential floors. While this is generous enough for most household activities, a large aquarium concentrates significant weight in a small footprint.

For most HDB flats, a tank up to 4 feet (120 cm) is generally safe when positioned correctly. Place large tanks against structural walls (not partition walls), ideally perpendicular to floor beams to distribute weight across multiple supports. If you want anything larger than 4 feet, it is worth consulting with a professional to assess your specific flat’s structure. Gensou’s custom aquarium service includes site assessment for larger installations.

Weight Calculator: Can Your Floor Handle It?

Use this simple method to estimate your aquarium’s total weight:

1. Water weight: 1 litre of water = 1 kg. Calculate volume in litres (L x W x H in cm, divided by 1,000). Fill level is typically 90% of the tank height.
2. Glass tank weight: Roughly 1-2 kg per 10 litres of capacity for standard glass tanks.
3. Substrate: Approximately 10-20 kg for a 2-foot tank, 20-40 kg for a 4-foot tank, depending on depth.
4. Hardscape: Rocks and driftwood add 5-20 kg depending on your layout.
5. Stand/cabinet: Typically 15-40 kg.

As a rule of thumb, a fully set up aquarium weighs approximately 1.2-1.4 times its water volume in kg, plus the stand weight. A 4-foot tank with 270 litres of water, substrate, hardscape, and a wooden cabinet will total roughly 350-400 kg.

Distributing Weight

The floor loading limit of 150 kg per square metre is based on average distributed load. A tank stand with a footprint of 120 cm x 50 cm (0.6 square metres) holding 380 kg creates a localised load of approximately 633 kg per square metre — well above the rated capacity. However, HDB floors are reinforced concrete slabs designed with substantial safety margins. In practice, 4-foot tanks are extremely common in HDB flats without issues.

To minimise risk:

• Place the tank against a structural wall, not a partition wall
• Position it as close to a wall as possible, where the floor slab is strongest
• Use a stand that distributes weight across its full footprint (not legs that concentrate weight at four points)
• Avoid placing tanks on upper-storey cantilever balconies

Quiet Filter Options for HDB Living

Noise is a genuine concern in HDB flats, where bedrooms share walls and floors transmit vibrations between units. The right equipment makes the difference between a silent aquarium and one that keeps you and your neighbours awake.

Noise Reduction Tips

• Place air pumps on a thick sponge or mouse pad to absorb vibrations
• Use check valves to prevent water backflow (which causes gurgling)
• Keep filter intakes and outlets submerged to eliminate splashing
• Choose canister filters from reputable brands (Eheim, Oase, Fluval) — they are engineered for silent operation
• Hang-on-back filters are quieter when the water level is kept high, minimising the waterfall drop

Best Fish Species by HDB Room

Living Room: Community Tank (60-120 cm)

The living room is the best location for a display aquarium in any HDB flat. It offers the most space, is typically the most structurally sound area, and allows the whole family and guests to enjoy the tank.

Recommended species for a living room community tank:

• Cardinal or neon tetras (school of 10-15): Stunning in groups. Electric blue and red colouration. Thrive in Singapore’s warm water.
• Harlequin rasboras (school of 8-12): Hardy, attractive, and well-suited to local water conditions.
• Corydoras catfish (group of 6+): Charming bottom dwellers. Active and social. Several species handle warm water well.
• Cherry barbs: Colourful, peaceful, and easy to keep.
• Honey gouramis: Beautiful centrepiece fish. Peaceful and suited to community tanks.
• Cherry shrimp: Add colour and constant activity. Excellent algae cleaners.

Bedroom: Nano Tank (20-35 cm)

If you want a tank in the bedroom, keep it small and quiet. A nano tank with a silent internal filter works well.

Recommended species for a bedroom nano tank:

• Betta (single male): Stunning colour, interactive personality. Thrives in small, quiet setups. No air pump needed.
• Chili rasboras (school of 8-10): Tiny, vibrant fish perfect for nano tanks. Very quiet inhabitants.
• Pygmy corydoras (group of 6): Miniature catfish that stay small and add activity without bulk.
• Cherry or crystal shrimp: Fascinating to watch, colourful, and zero noise.

Study/Home Office: Desktop Tank (25-45 cm)

A desk-mounted tank adds life to a home office without taking up floor space.

Recommended species for a desktop tank:

• Betta: The ultimate desk fish. Interactive and visually striking.
• Endler guppies (small group): Tiny, brilliantly coloured, and constantly active.
• Celestial pearl danios (school of 6-8): Galaxy-like patterning in a tiny package.
• Amano or cherry shrimp: Low bioload, interesting behaviour, minimal equipment needed.

Where to Place Your Tank in an HDB

• Living room: Ideal. Most space, strongest floor area (typically near structural walls), best visibility.
• Study/spare room: Good option for hobby tanks. Usually quieter for fish keeping.
• Bedroom: Acceptable for nano tanks with quiet equipment only.
• Kitchen: Avoid. Cooking fumes, heat, and grease are harmful to aquarium inhabitants.
• Corridor: Avoid. HDB common corridors are shared spaces. Tanks placed outside your unit breach fire safety regulations and can obstruct escape routes. Keep tanks inside your flat.
• Balcony: Possible for outdoor-tolerant species, but direct sunlight causes extreme algae and temperature fluctuations. Shield from direct sun and rain.

For guidance on choosing the right tank dimensions for your available space, see our guide on how to choose an aquarium size.

Electrical Considerations

A typical aquarium setup requires power for several devices running simultaneously:

• Filter: 5-30 watts (runs 24/7)
• LED light: 10-50 watts (6-8 hours daily)
• Heater (if needed): 50-200 watts (thermostatically controlled)
• Air pump (if used): 3-10 watts (runs 24/7)
• CO2 solenoid (if planted tank): 3-5 watts (6-8 hours daily)

Total draw for a typical community tank is modest — roughly 20-80 watts continuously, with occasional peaks if a heater cycles on. This is well within the capacity of a standard HDB power point. However:

• Use a surge protector/power strip rated for the combined load
• Keep all electrical connections above water level to prevent water damage
• Use drip loops on all cables — a cable that dips below the socket level before connecting ensures that any water running down the cable drips off at the lowest point rather than entering the socket
• Consider a timer for lights and CO2 to automate the daily schedule

Neighbour Considerations

Living in close proximity to neighbours means being mindful of how your hobby might affect those around you.

• Noise: Air pumps and vibrating equipment can transmit through HDB floors and walls. If your downstairs neighbour complains about a buzzing sound, your air pump may be the culprit. Place vibrating equipment on anti-vibration mats and consider switching to a canister filter that does not require an air pump.
• Water leaks: A tank failure or spillage during maintenance can damage the flat below. Use a drip tray or mat under your tank, and always have towels ready during water changes. For large tanks, consider waterproof matting under the stand.
• Smell: A well-maintained aquarium is odourless. If your tank smells, there is a water quality or maintenance issue that needs addressing. Neighbours should never be able to detect your aquarium by smell.

Frequently Asked Questions

Is there a maximum tank size allowed in HDB flats?

HDB does not specify a maximum aquarium size in their flat regulations. The practical limit is determined by floor loading capacity (150 kg/sqm rated live load), available space, and access (getting a large tank through HDB corridors and lifts). Most hobbyists find that a 4-foot (120 cm) tank is the practical maximum for comfortable setup and maintenance in a typical HDB flat. Anything larger requires careful planning around placement, access, and weight distribution.

Can I keep an arowana in my HDB flat?

Technically yes, but an arowana requires a minimum 5-foot (150 cm) tank, and larger is strongly recommended. A tank this size filled with water, substrate, and a sturdy stand will weigh 500 kg or more. This pushes the boundaries of HDB floor loading, particularly on upper floors. If you are set on keeping an arowana, position the tank against a structural wall on the lowest floor possible, and consult with a professional about your specific flat’s suitability. Gensou’s team can advise on custom large tank installations.

Do I need a chiller for my HDB aquarium?

Most common tropical fish thrive at 26-30 degrees Celsius, which is within the normal temperature range of an un-air-conditioned HDB flat. You generally do not need a chiller unless you keep temperature-sensitive species (crystal shrimp, certain plecos, discus) or your tank regularly exceeds 32 degrees Celsius during hot spells. If your flat has air conditioning running regularly, your aquarium water may actually be too cool for some tropical species — a basic heater set to 26 degrees provides stability.

What if my HDB flat has limited floor space?

Consider a wall-mounted or shelf-mounted nano tank (20-30 cm). These take up zero floor space and can house bettas, shrimp, or small schooling fish beautifully. Another option is a tall, narrow tank (sometimes called a column or portrait tank) that has a smaller footprint than a standard rectangular tank. Just be aware that tall, narrow tanks have less surface area for gas exchange and are harder to aquascape, so they suit fewer fish species.

Whatever your HDB setup, the team at Gensou can help you choose the right tank, fish, and equipment for your space and budget. With 20 years of experience setting up aquariums in Singapore homes — including countless HDB flats — we understand the practical challenges and how to work around them. Visit us at 5 Everton Park or get in touch for personalised advice.

Related Reading

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• 10 Beginner Aquarium Mistakes and How to Avoid Them
• Top Aquarium Mistakes in the First Month and How to Avoid Them