Water Tank Capacity Options For A Small Family

Different families require different things from their water tanks. This could be determined by where they live, the water situation in that part of Australia, and also the size of the small family. There are places that require you to install a decent sized water tank to allow for water harvesting, and to store as much water as you can in case of drought.

The size of your family will also determine what size of tank you need. The more the people there are in a home, the more divergent their water requirements, and the more strain on your water tank.

However, this doesn’t mean you should go out there and buy the biggest tank you can find. Before purchase and installation, there are certain things you need to look at. These factors will help you choose the kind of tank you need. They include:


Available space is a strong determinant. At the very least, it forces you to figure out whether you will install an above ground or underground tank. It also makes you choose the shape of the tank more carefully. Round tanks tend to occupy more space than slim-line tanks, since they tend to be wider. However, they are structurally stronger and cheaper, which makes them at great option. Round tanks range in capacity from 200 litres to 25,000 litres, while slim-line tanks typically go from around 300 litres to 3,000 litres.


Depending on where you and your family live, your water tank needs may vary. To understand this, you need to look at typical roof sizes and rain patterns. Square footage or cubic foot measurements of your roof determine how much rain you can harvest.

This is because rain that falls on the walls or ground can’t effectively be collected. You can only harvest what slides off the roof, down the gutters, and into your rainwater tank. Therefore a 3-bedroom houses with their 150 cubic meter roofs will definitely require a smaller water tank than a 5-bedroom house which will have twice the roof size.

People that live in certain areas have specific storage needs based on the frequency and volume of rainfall. For instance, people living in Victoria, Tasmania and much of New South Wales experience relatively constant rainfall throughout the year.

Their water tank needs differ greatly from people who live in the Mediterranean climates of Western Australia, where rainfall is significant over the winter, but summers are relatively dry. Their needs will also be different from people living in central Australia, where the conditions are arid and characterised by low rainfall all year round.


Your water usage as a family also determines what size tank you should get. For instance, a small family who intend to use their water to flush a Water Efficiency Labelling and Standards (WELS) rated dual-flush toilet, wash their car, and maybe clean their boat once a fortnight will use less water than a larger family with the same water usage needs. By contrast, a small family that uses more water may need a larger tank than a big family that skimps on cleanliness and gardening.

What are the options?

In climates that receive lower annual rainfall, it is best to consider a round water tank with the 10,000 litre capacity. If you are low on space, you could opt for the 3,000 litre slim-line tank, although the benefits will clearly not be the same. This will enable you to collect as much water as you can, to tide you over until the next rain cycle.

Small families in areas that receive sizable rainfall may not have dire storage needs, since their rainwater supply is consistent. For those who would like to maximize their rainwater collection, they should consider larger tanks.

A good example is the 13,500 litre round tank, and the 18,200 litre one as well. For those whose water needs are a lot more divergent, they could look at the 22,700 litre variation of the round tank. However, they could do just as well with an 10,000 litre or 11,500 litre tank since the rain will regularly refill the tank.

When shopping around for a water tank, remember to always pay attention to price, quality and the range of after sales services. These include delivery, installation and any other needs after that, such as warranties and repair.