In the world of rainwater harvesting and liquid storage, two terms are often thrown around interchangeably: poly tanks and plastic tanks. While they may seem like the same thing at a glance, there are subtle—but important—differences that every homeowner, farmer, or business owner should understand before investing in a tank.
This blog post clears up the confusion, explains the differences (and similarities), and reveals why the term poly water tank represents a far more specific and reliable product—especially when you’re buying from a trusted Australian supplier like The Water Tank Factory.
What Are Plastic Tanks?
The term “plastic tank” is a general label used to describe any tank made from a type of plastic material. These can include:
Polyethylene (PE) – the most common and preferred plastic for water storage tanks
PVC (Polyvinyl Chloride) – typically used in plumbing but sometimes for containers
Polypropylene (PP) – used in some industrial tanks
Acrylonitrile Butadiene Styrene (ABS) – rare in tank construction
The problem with the term “plastic tank” is that it’s vague. It doesn’t tell you what kind of plastic is used, how it’s manufactured, or whether it’s safe for drinking water.
In other words, not all plastic tanks are created equal.
What Are Poly Tanks?
“Poly tanks” is short for polyethylene tanks, and in the Australian market, this is a big deal.
Polyethylene is:
- BPA-free
- UV-stabilised
- Food-grade
- Flexible and impact-resistant
- Resistant to corrosion, algae, and bacteria
The Water Tank Factory’s New Generation™ Poly Water Tanks are manufactured using rotational moulding technology, which ensures:
- Even wall thickness
- Exceptional durability
- Superior resistance to cracking and sun damage
These tanks meet Australian Standards (AS/NZS 4766) for polyethylene storage tanks and come with a 20-year warranty, so you know you’re getting quality.
Explore our Poly Water Tank Range
Key Differences Between Poly and Generic Plastic Tanks
| Feature | Poly Tanks (Polyethylene) | Generic Plastic Tanks |
|---|---|---|
| Material Type | Food-grade polyethylene | Varies (may be lower-grade plastics) |
| UV Stabilisation | Yes | Not always |
| Water Safety | Certified for drinking water | May not meet potable standards |
| Durability | High impact and UV resistance | Varies; often thinner and more brittle |
| Warranty | 20 years (with The Water Tank Factory) | Often shorter or none |
| Manufacturing Standard | AS/NZS 4766 Compliant | Not always compliant |
| Ideal Use | Domestic, farming, commercial | May be unsuitable for long-term storage |
The takeaway? All poly tanks are plastic tanks—but not all plastic tanks are true poly tanks. And that’s where many buyers get misled.
Why Australians Trust Poly Tanks
Australia’s harsh climate demands tanks that can survive intense sun, fluctuating temperatures, and heavy rainfall. Poly tanks are built to handle it all.
They’re popular because:
- They’re lightweight and easy to install
- They come in a wide range of shapes, sizes, and colours
- They can outlast many steel or concrete options when properly maintained
At The Water Tank Factory, our poly tanks come in round, slimline, underdeck, underground, and custom shapes to suit every space and application—from backyard rainwater harvesting to commercial liquid transport.
Are There Downsides to Poly Tanks?
All materials have pros and cons. In some cases, customers may prefer steel water tanks for aesthetic appeal or larger capacities. However, poly tanks are:
- Lower in cost
- Less prone to corrosion
- Easier to transport and install
And thanks to The Water Tank Factory’s high shot weight per tank, our poly tanks feature thicker, more durable walls than many competitors—meaning longer life and greater peace of mind.
How to Spot a High-Quality Poly Water Tank
Not all poly tanks are equal, even if they’re made from polyethylene. Here’s what to look for:
✅ Certified food-grade plastic
✅ UV-stabilised resin
✅ Even wall thickness (rotationally moulded)
✅ Compliance with Australian standards (AS/NZS 4766)
✅ Long warranty period
✅ Made in Australia for Aussie conditions
The Water Tank Factory ticks every one of these boxes and offers 1,745 size, shape, and colour combinations—one of the largest ranges in Australia.
What Size Poly Tank Do You Need?
Poly tanks are available in a massive range of sizes:
200L–2,000L: Ideal for small gardens, balconies, or urban homes
3,000L–5,000L: A great mid-range size for rainwater use in toilets and laundry
10,000L–27,000L+: Perfect for rural homes, farms, and businesses
Need help choosing? Call our friendly team or use our Water Tank Calculator to estimate your ideal size based on rainfall and roof area.
Are Poly Tanks Recyclable?
Yes! The Water Tank Factory’s poly tanks are 100% recyclable at the end of their life. As sustainability becomes a higher priority for Aussie households and businesses, choosing a recyclable tank is a smart move.
Still Unsure? Here’s How to Decide
Ask yourself:
- Do I want a tank certified for safe, potable water?
- Do I need a tank that won’t rust, crack, or degrade in the sun?
- Am I looking for value, performance, and a long warranty?
If the answer is yes, then you’re not just looking for a plastic tank—you’re looking for a poly tank from The Water Tank Factory. Call our team today on 1300 826 532 or visit https://watertankfactory.com.