Rainwater Tank FAQ

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2300L slimline 30000L round and 22000L Round pictured


Master water tank manufacturers since 1976

For a single detached house we advise a minimum 22,000L capacity.

For all other class 1 dwellings we advise a minimum 30,000L capacity.

For rural dwellings not serviced by town water we advise a minimum 44,000L capacity. If needed this can be accommodated for by more than one tank.

Follow this link to an independent site run by the ATA to help you calculate a tank size for your site: The ATA Tankulator

In the past, steel tanks were made from galvanised iron or zincalume, which corroded easily and gave them a short lifespan.

Aquaplate is a superior steel tank material designed and manufactured in Australia by Bluescope Steel, offering a noticeable difference in drinking water quality.

All Aquaplate steel has a food-grade polymer lining bonded to it during its manufacture, making it waterproof and non-corrosive.

Aquaplate tanks consistently outlast Poly tank lifespans by 20 to 30 years.

We recommend the use of Aquaplate tanks for any drinking water needs, as they provide a better quality, cleaner tasting water.

Unfortunately Poly tanks are more susceptible to heat and therefore have a greater risk of bacteria build-up.

Poly tanks, even when UV-stabilised, will deteriorate and weaken after prolonged UV and heat exposure over time. If you can see your Poly tank losing colour, going white, or becoming veiny, this is your tank deteriorating.

For garden or irrigation use, either a Poly or Aquaplate tank would suffice, depending on your size and longevity requirements. Either type of tank is also ideal for grey water storage.

If you are in a rural area or an area prone to storm damage, Aquaplate tanks are ideal as they will not catch fire, warp or melt. Poly tanks are susceptible to storm damage as they are weakened by hot and cold weather fluctuations and may burst in the case of high water pressure during storms or floods.

Aquaplate tanks can also be built to custom-sizes, while Poly tanks are restricted to set dimensions as they are built in moulds.

Our Aquaplate tanks come with a 20 year warranty, and our poly tanks a 10 year warranty.

Both Poly and Aquaplate tanks have their benefits, but do bear in mind that while Aquaplate tanks are recyclable, most landfills or rubbish dumps will not accept Poly tanks.

Round tanks have a larger capacity and are more economical per litre of collection.

The slimline is more expensive, but offers clever space saving solutions,designed to fit underneath or along side of your house or shed, or in more awkward spots.

Unless otherwise advised, 
1 x  500mm Qld Reg mosquito proof strainer and light guard

1 x 90mm mosquito proof overflow with removable screen

1 x 25mm outlet (BOSS)

1 x 25mm Ball Valve (TAP), all including GST.

*Delivery costs may apply in addition depending on your location.


NTM manufactures rainwater tanks and supplies superior rainwater harvesting solutions for new and existing buildings.

We proudly offer customers short turnaround times from initial consult and order to delivery and installation at their site.

We want to build honest and meaningful relationships with our customers by sharing our extensive knowledge and understanding of the rainwater tank industry.


We are manufacturers of Aquaplate Steel Rainwater tanksand distributors of orange pumps and Great Northern tanks.



National Tank Makers offers customers an extensive range of high-quality steel water tanks and landscaping supplies.


Aquaplate steel tanks

Our corrugated water tanks are made from Bluescope’s Aquaplate specialised modern steel and are available in various sizes and colours. 


Garden Beds

NTM’s fully assembled garden bed water tanks are a durable, aesthetically pleasing option for displaying and maintaining your garden. 

Garden Soil

Landscape supplies

NTM’s premium-quality landscaping supplies accommodate casual weekend gardeners to professional landscapers. 

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