What Size Water Tank Do I Need?
Jump to sections – this article will cover
How Much Water Do You Need? | What Size Tank Do You Need? | Water Tank Size & Dimensions | Rainwater for all Your Needs? | How Much Can You Save? | Water Tank Costs | Best Water Tanks To Buy
How Much Water Do You Need?
Rain Catchment Calculator
How Much Rainwater Can You Harvest? Use our rain catchment calculator to find out
Water Tank Dimensions and Sizes
Slimline Water Tanks
However, there is a caveat: the maximum water storage for a single slimline water tank is 8,500 litres. Fortunately, there’s a way around this – just link up multiple tanks side by side to increase water storage capacity.
Please note: not all dimension combinations are available
Slimline Water Tank Dimensions & Examples of Sizes | Capacities
The right size water tank for you will depend on the rainwater storage capacity you need, as well as the space you have available. For a full list of all our Slimline Water Tank Sizes & Dimensions visit our Steel Water Tank Pricing Page.
| Capacity (litres) | Width x Length x Height (mm) |
| 1,583 | 700 x 1600 x 1560 |
| 2,090 | 650 x 2200 x 1560 |
| 2,145 | 850 x 1800 x 1560 |
| 3,065 | 850 x 2100 x 1880 |
| 3,206 | 850 x 2600 x 1560 |
| 3,251 | 650 x 2800 x 1880 |
| 3,322 | 750 x 3000 x 1560 |
| 5,067 | 700 x 4000 x 1880 |
| 5,088 | 1150 x 2600 x 1880 |
| 5,119 | 1150 x 3100 x 1560 |
| 5,352 | 950 x 3200 x 1880 |
| 7,712 | 1150 x 3100 x 2350 |
| 8,523 | 1150 x 3400 x 2350 |
Round Water Tanks
Round water tanks can store up to 30,000 litres of water and are ideal where you have plenty of space and where you want a large volume of water – they’re a regular sight in country towns, where they’re helping farmers to combat drought, and significantly reducing the load on mains water supply in regional areas. But if you’ve got a large-enough backyard, they’re a great choice for urban and suburban homes as well!
Please note: not all dimension combinations are available
Round Water Tank Dimensions & Examples of Sizes | Capacities
The right size water tank for you will depend on the rainwater storage capacity you need, as well as the space you have available. For a full list of all our Round Water Tank Sizes & Dimensions visit our Steel Water Tank Pricing Page.
| Capacity (litres) | Diameter x Height (mm) |
| 2,071 | 1300 x 1560 |
| 3,120 | 1300 x 2350 |
| 3,138 | 1600 x 1560 |
| 3,324 | 1500 x 1880 |
| 4,903 | 2000 x 1560 |
| 5,332 | 1900 x 1880 |
| 5,336 | 1700 x 2350 |
| 7,814 | 2300 x 1880 |
| 10,308 | 2900 x 1560 |
| 10,635 | 2400 x 2350 |
| 10,768 | 2700 x 1880 |
| 15,015 | 3500 x 1560 |
| 15,126 | 3200 x 1880 |
| 15,528 | 2900 x 2350 |
| 18,095 | 3500 x 1880 |
| 20,108 | 3300 x 2350 |
| 20,484 | 2900 x 3100 |
| 22,619 | 3500 x 2350 |
| 23,407 | 3100 x 3100 |
| 24,942 | 3200 x 3100 |
| 25,278 | 3700 x 3350 |
| 29,838 | 3500 x 3100 |
One Big Tank or Several Smaller Ones Linked Together?
From our many years of experience in supplying and installing water tanks, we have found that having three round tanks holding 29,000 litres each (total 87,000 litres) will easily keep even a large family in water all year round.
Can You Use Rainwater Tanks For All Your Water Needs?
80% of households with rainwater tanks consider the volume of water they collect in their tanks to be sufficient for all their needs, including:
- Drinking water
- Garden watering
- Toilet flushing
- Laundry usage
- Replenishing domestic pools or spas
- Car washing
- Supplying the hot water system
- Thermal buffers to insulate houses
- Ventilation for buildings
- Protecting homes from bushfires
Rainwater that you collect from a well-designed and operated system can be suitable for any and all domestic water uses. For example, you can use you tank water for your garden and some indoor uses (toilet flushing & showering), while still sourcing your drinking water from your water supply. And if you want to reduce your reliance on mains water even further, check out our Rainwater Tank Filter System which can make your tank water 100% safe for drinking as well.
How Much Can You Save?
| Household Size | Average Per year |
| 1 | $884 |
| 2 | $1,072 |
| 3 | $1,248 |
| 4 | $1,292 |
| 5 | $1,488 |
So, What About The Upfront Cost Of A Water Tank?
Is a water tank a good investment? How long does it take to pay your water tank back? All good questions. With around half of Brisbane homes having a water tank nowadays, water tanks are a trend that’s really caught on. And it’s not just about the environmental impact; they’re actually a great buy.
Let’s say that you spend $4,296 on a 3500 x 1560 round water tank with a 15,015L capacity (sounds oddly specific? That’s because it’s an actual water tank we sell – head to our pricing page). If you use 15,000L per month for 3 people, and you save $1,248 per year, your water tank will pay for itself in less than four years – and with a 30-year warranty, you can expect another 21 years of savings. #betterthanbitcoin? We think so!
What Is The Best Water Tank To Buy?
You’re already asking yourself the question “What size water tank do I need?”, but size isn’t the only factor to think about. Cost is another important factor, but remember, there’s a trade-off – a water tank made of cheaper materials like poly (i.e. plastic) will degrade faster and so has a shorter lifespan, whereas for a bit of a higher upfront cost, you can choose a steel water tank with a 30-warranty and enjoy substantial savings on your water bills for years to come.
Other than the materials, the shape of a water tank will affect the pricing – slimline water tanks will generally be more expensive than a round water tank of equivalent sized. That’s because unlike round water tanks, slimline water tanks require internal reinforcing rods to keep their sides stable when the tank is full of water. This makes these water tanks slightly more expensive, but on the other hand, they do have the advantage that they can be fitted into narrow spaces.
For more information check out our article: Best materials for water tanks