Once you have decided upon the material type of rainwater tank that you will purchase, then you will need to decide upon the capacity size, shape and colour.
What water tank colours are available?
While steel water tanks are often limited to a steel finish, perhaps in different textures, other materials such as AQUAPLATE® and poly water tanks support a range of colours. Many manufacturers provide a range of COLORBOND® colours to select from.
Water tanks made from polyethylene allow for the widest range of colours, meaning you can more easily complement your shed, house, gardens or the immediate environment.
Can the colour of the tank effect the water?
There are also practical reasons for choosing a certain water tank colour. Darker coloured tanks will absorb more heat from the Sun, which in turn means your rainwater will be warm or hot. This will be especially true if your water tank won’t be sheltered from the Sun. This could be a benefit, or if you will drink your rainwater and prefer a cool and more refreshing taste then a lighter coloured tank might be more appropriate.
Can sunlight get into lighter coloured poly tanks?
If light can get into your water tank it can cause algae to grow which can effect your water quality if you plan to drink it.
However, the colour of the tank would not prevent sunlight from entering as much as the wall thickness. The Australian water tank standard AS/NZS 4766 sets guidelines for the minimum wall thickness for polyethylene tanks. If your tank is certified to this standard then light cannot penetrate the thick plastic and your water will be safe.
Will my poly tank colour fade?
Another concern is whether your tank colour will fade in the Sun. Poly storage tanks can have UV stabilisers added in the mix when a polyethylene tank is moulded.
The use of stabiliser resin during the moulding process can inhibit or absorb the harmful UV light that would otherwise cause the plastic to fade. One way you can quickly tell if a tank is UV stabilised is by its finish – a tank with a high glossy shine is often UV stabilised whereas a tank with a matte finish is not.
Is it safe to paint a poly water tank?
It is also important to get the choice of colour right from the very beginning. Painting your tank will add additional expensive compared to getting your tank made in the correct colour. Keep in mind that some steel tanks require specific paints so as to not negatively react with the metal. Also many paints contain solvents and materials that can leak into the water supply, so paints and materials used in tanks must also comply with government standards for the storage of potable water.