Size up your stormwater tank
Council stormwater rules differ from region to region, so the tank you need depends on which rule applies to your site. Promax detention tanks and sizing calculators take the guesswork out of the number.
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Articles | Knowledge Hub
Make Better Decisions About Water Storage
Practical, plain-language guidance on choosing, installing and maintaining water storage, written by the Promax team.
How to Get the Cleanest Water From Your Rainwater Tank
Four accessories keep rainwater clean in two stages: filtering debris before it reaches the tank, then drawing from the cleanest layer inside it. Here is what each one does, and which pair matters most.
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Buyers Checklist
Ten questions worth asking before you buy a water tank, and where to find the answer to each one. Get these right up front and the rest of the decision follows.
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Ten Reasons to Purchase a Promax ENDURO Water Tank
The Promax ENDURO is a one-piece corrugated tank carrying a 20 year warranty, available in seven colours, and rated to be buried up to 1 m without losing that warranty. Here is what the range gives you.
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Which is the strongest water tank?
The Promax corrugated ENDURO is the strongest New Zealand-made plastic water tank. Continuous sidewall corrugation and one-piece moulded construction let it be buried up to a metre and back-filled against, with a full guarantee of 20 years.
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Underground Stormwater Tanks – Which is best, concrete or plastic?
Rigid concrete tanks cracked in the Christchurch and Kaikoura earthquakes, and Promax replaced many of them. We have had no recorded failures of our plastic tanks after those events, which is the clearest answer we can give on material choice.
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Buying the right water tank
Size, budget, site, material, maintenance and consent: the pieces of the tank buying puzzle, and how to weigh each one before you order.
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B2/AS1 Requirements for NZ Building Projects
Clause B2 of the New Zealand Building Code sets durability standards for building elements, and B2/AS1 is the acceptable solution beneath it. Here is what it covers and how compliance is demonstrated.
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Plumbing Layout and Council Compliance | Using Rainwater at Home
Roof to tank, tank to pump, pump to changeover device: how a rainwater reuse system is plumbed, the backflow prevention it needs, and what a council wants documented.
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Selecting the Right Pump and Changeover Device | Using Rainwater at Home
Part of the Using Rainwater at Home series. How to match a pump and changeover device to the house, and when a pre-plumbed tank and pump combo is the simpler option.
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Maintenance, Troubleshooting & Handover | Using Rainwater at Home
Keeping a home rainwater reuse system reliable: the routine checks, the signage that matters, how to diagnose the common faults, and what a good handover includes.
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How Tank-to-Mains Systems Work | Using Rainwater at Home
What happens when your rainwater tank runs empty? A changeover device switches the house to mains and back without you touching a thing. Part one of the Using Rainwater at Home series.
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Explore Our Range
Shop Popular Categories
Browse Promax tank categories for residential, rural, commercial, and specialised applications.
Water Tanks
Reliable Storage
Water Tanks
Durable above-ground water tanks for rural, residential, and commercial storage.
Underground Tanks
Space Saving
Underground Tanks
Underground water storage for sites where space, access, or visibility matters.
Slimline Tanks
Built for Tight Spaces
Slimline Tanks
Narrow-profile tanks designed for homes, boundaries, and other restricted spaces.
Industrial Tanks
Heavy Duty Solutions
Industrial Tanks
Specialised tanks for demanding commercial, industrial, and process applications.