The Promax Underground Stormwater / Wastewater tanks are suitable for the retention or detention of stormwater or the storage of potable water.
The plastic detention tanks are fully tested and designed to withstand ground and water pressure at depth.The Promax Underground tank is engineered by geotechnical experts and Finite Element Analysis tested (FEA).
Distinctive Benefits for:
- Stormwater retention, detention and Wastewater storage
- Suitable to be installed under driveways, footpaths, car parks, forecourts and much more
- Save time and money with multiple inlet/outlet plumbing ports
- Vehicular Traffic Tested
- Non Vehicular Traffic - Tanks in non-critical areas can be placed at any depth that is required
2000l -
Code | Description | Capacity(L) | Diameter(mm) | Length(mm) | Weight(kg) | Manhole Dia(mm) |
---|---|---|---|---|---|---|
UX0702000 | XPRESS Underground Tank 2,000 Ltr 750mm Dia | 2000 | 750 | 3835 | 115 | 600 |
3000l -
Code | Description | Capacity(L) | Diameter(mm) | Length(mm) | Weight(kg) | Manhole Dia(mm) |
---|---|---|---|---|---|---|
UX0703000 | XPRESS Underground Tank 3,000 Ltr 750mm Dia | 3000 | 750 | 4960 | 165 | 600 |
4000l -
Code | Description | Capacity(L) | Diameter(mm) | Length(mm) | Weight(kg) | Manhole Dia(mm) |
---|---|---|---|---|---|---|
UX0704000 | XPRESS Underground Tank 4,000 Ltr 750mm Dia | 4000 | 750 | 7580 | 210 | 600 |

About Promax
Promax water tanks are built tough for New Zealand conditions, combining strength, durability, and long-lasting performance. The premium corrugated ENDURO range delivers maximum reliability over many years, while the XPRESS range provides the same trusted Promax quality at a more affordable price point.
Available in a wide range of sizes, shapes, and colours, Promax tanks are designed to blend into your property and meet any water storage need – from residential rainwater harvesting to commercial or agricultural use. With options for both above-ground and underground installation, there’s a Promax tank for every project.
Shop the full Promax range at Turfrey – your trusted supplier of water storage solutions in New Zealand.
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