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Steel and other metal water tanks have long been a popular choice.  

And with new colours, shapes and sizes becoming increasingly available, it looks like they’ll continue to be a popular choice for many years to come.  

Historically, metal water tanks were made from rolled sheets of galvanised iron, riveted and soldered to prevent leaking. They were the “backbone” of rainwater storage in many parts of the world, including Australia.  

Today, many metal tanks are made from ZINCALUME® or AQUAPLATE®. 

Installed on a concrete base or approved tank stand, these tanks are often used for aboveground water tank installations.

Traditional galvanised tanks  

Galvanising is the process of applying one or more metals to another metal. The humble “tin” tank of the past was often a galvanised tank made from zinc galvanised to steel. These galvanised tanks could be soldered with a combination of lead and tin which was melted with a hot iron and applied to a joint prepared with spirits of salts. Because these metals were similar to each other, they were deemed compatible and adhered to one another under heat.  

ZINCALUME® roofs & tanks 

BlueScope Steel Ltd.’s ZINCALUME® is best known as the high tensile roofing product that revolutionised the roofing industry. After all, it was strong and came in long, one-piece sheets that reached from the roof ridge to the gutter without a join.  

However, the emergence of ZINCALUME®, which is primarily a zinc and aluminium mix galvanised to steel, spelled trouble for traditional galvanised water tanks. Water travelling from the ZINCALUME® roof to the galvanised tank caused the tank to rust and even collapse. This occurred because the process of galvanic corrosion, whereby different metals are joined together by a medium such as water, accelerates corrosion. In such situations, the less “noble” metal corrodes and rusts – and that meant the galvanised tank fell victim.  

While ZINCALUME® roofs and galvanised tanks cannot mix, however, ZINCALUME® roofs and ZINCALUME® tanks both work very well together. Most ZINCALUME® tanks are “plain” metal water tanks with no added colour.  

AQUAPLATE® tanks  

Today, many steel water tanks are made from AQUAPLATE® – another trademark of BlueScope Steel Ltd.  

AQUAPLATE® tanks are top-of-the-range metal tanks. They have a food-grade polymer skin bonded to their inner surface to help ensure your water tastes clean and fresh and remains free from any tainting from the tank itself. Their 20 year warranty covers corrosion and perforation, although conditions apply.  

Large metal tanks  

Metal tanks are also available using a modular construction system which ensures strength and water quality and makes delivery onsite more manageable. These modular tanks can be built to store significant water volumes, making them popular in rural and commercial applications.  

The right tank for you 

Strong and durable, metal water tanks are a popular aboveground tank choice.  

They’re also repairable, as seams can be resealed by the manufacturer.  

Of course, it’s not just tank materials you need to be concerned about – you should also consider your ideal tank size and designing your Rain Harvesting system to provide cleaner water and lots of it.