Water Tank Sizes

Find the Perfect Water Tank Sizes for Your Needs

Choosing the right water tank size is easier than you think.

Whether you’re looking to water your garden, reduce your mains water usage, or go fully off-grid, water tank sizes are available for you to choose. At Wholesale Water Tanks, we stock a wide range of durable, Australian-made water tanks to suit every home, property, and project.

What Will You Use Your Tank For?

Your ideal tank size depends on what you’re using it for:

Garden use only? A compact 2,000L to 5,000L tank could be perfect.
Laundry, toilet, and garden? You’ll likely need between 5,000L and 10,000L.
Full household or rural supply? Consider 22,000L or larger.

We’re helping Australians choose the right tank size and we’re here to help you too.

Common Water Tank Sizes

Tank Size	Ideal for	Type
1,000 to 3,000L	Small gardens, patios, limited space	Slimline or under-deck
5,000–10,000L	Suburban homes, moderate usage	Round or slimline
10,000–22,000L	Larger homes, partial off-grid	Round tanks
22,000L+	Off-grid living, rural properties, firefighting	Rural round tanks

Frequently Asked Questions

What size water tank do I need for my home?

The ideal size depends on your roof catchment area, local rainfall, intended water usage (e.g. garden, toilet, laundry), and space available. As a guide, many Australian households opt for tanks between 5,000L and 10,000L for general use. Rural properties or those aiming for self-sufficiency often choose 20,000L+ tanks.

How do I calculate the right water tank size for my property?

Start with your average rainfall (mm/year) × roof catchment area (m²) × 0.9 (runoff coefficient). Then, assess your daily water needs. Many tank suppliers offer online calculators to help determine the ideal size.

What size tank is best for garden use only?

If you’re using your tank for watering the garden, a 2,000L to 5,000L tank is typically sufficient, depending on garden size and watering frequency. Slimline or under-deck tanks are great space-saving options for urban homes.

Can I install multiple smaller tanks instead of one large one?

Yes, connecting multiple smaller tanks can be a smart solution if space is limited or if you want to stage your investment. Just ensure they’re properly connected and level for even distribution.

Are there standard water tank sizes in Australia?

There’s no single standard, but common sizes include:

1,000L – 3,000L (compact/slimline tanks)
5,000L – 10,000L (mid-size for domestic use)
20,000L – 50,000L+ (large rural or commercial tanks)

What size tank do I need to go off-grid?

To live off-grid or meet bushfire requirements, you’ll likely need a 22,000L+ tank, or multiple tanks. Some regions in Australia mandate minimum storage volumes for firefighting. Check with your local council or CFA/RFS for specifics.