Large Water Tanks | 10,000L+ Large Water Tanks | 10,000L+

Large Water Tanks | 10,000L+

Promax large plastic water tanks are available in capacities from 10,000L to 30,000L, giving farms, lifestyle blocks, commercial sites, and large households a reliable water supply without depending on mains. The range includes ENDURO tanks with corrugated walls for added rigidity and up to 7 colour options, along with XPRESS tanks with smooth walls that offer excellent value.

Both series are manufactured from polyethylene, compliant with AS/NZS 4766, carry a 20-year pro-rata warranty, and are made in New Zealand at our facilities in Kerikeri and Rangiora.

Clear all
25,000L Water Tank - XPRESS in Mist Green, Image 1

25,000L Water Tank - XPRESS

$3,412.00
$3,412.00
30,000L Water Tank - XPRESS in Mist Green, Image 1

30,000L Water Tank - XPRESS

$3,890.00
$3,890.00
25,000L Water Tank - ENDURO in Mist Green, Image 1

25,000L Water Tank - ENDURO

$4,226.00
$4,226.00
+3
30,000L Water Tank - ENDURO in Mist Green, Image 1

30,000L Water Tank - ENDURO

$5,104.00
$5,104.00
+3
10,000L Water Tank - XPRESS in Mist Green

10,000L Water Tank - XPRESS

$2,372.00
$2,372.00
10,000L Water Tank - ENDURO in Mist Green

10,000L Water Tank - ENDURO

$3,129.00
$3,129.00
+3
15,000L Water Tank - XPRESS in Mist Green, Image 1

15,000L Water Tank - XPRESS

$2,705.00
$2,705.00
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Why You Need a Large Water Tank

A farm without its own water reserve depends on the weather and on mains supply. When the council imposes water restrictions, when a main breaks, when a dry spell stretches into months, stock still needs water every day. An above ground water tank solves this without excavation.

On rural properties, mains water is often unavailable altogether. The only source: rainwater, a bore, or a stream. A farm water tank of 10,000L or larger provides a reserve that carries through dry weather.

On large commercial sites (wineries, packhouses, dairy farms), water is needed for process use, washdown, and firefighting. A single 30,000L water storage tank replaces several smaller ones and simplifies the system.

When a large tank is the right solution:

  • Farm or rural property with no mains water connection
  • Stock water reserve needed for the dry season
  • Commercial site requires high volume for process water, washdown, or firefighting
  • Rainwater tank needed to collect from a large roof area
  • One large tank instead of several small ones to simplify the system

When a Large Tank Is the Right Solution:

A tank of 10,000L or above provides independence. Water for stock, irrigation, household use: all from one source, with no reliance on weather or external supply.

On commercial sites, a large tank works as buffer storage. When peak demand exceeds the capacity of a pump or bore, the tank makes up the difference. This allows smaller pump equipment and reduces energy costs.

A polyethylene water tank does not rust and does not react with water. The one-piece construction reduces maintenance requirements. 20-year warranty on tanks 10,000L and above.

What a Large Water Tank Gives You

A tank of 10,000L or above provides independence. Water for stock, irrigation, household use: all from one source, with no reliance on weather or external supply.

On commercial sites, a large tank works as buffer storage. When peak demand exceeds the capacity of a pump or bore, the tank makes up the difference. This allows smaller pump equipment and reduces energy costs.

A polyethylene water tank does not rust and does not react with water. The one-piece construction reduces maintenance requirements. 20-year warranty on tanks 10,000L and above.

What Capacity to Choose

The range covers 10,000L to 30,000L. The right capacity depends on the number of people, stock numbers, roof collection area, and intensity of use.

For calculation: 1 mm of rainfall on 1 m2 of roof yields 1 litre of rainwater. A house with a 200 m2 roof collects 200 litres from every millimetre of rain. Specific requirements depend on the number of people, stock numbers, and irrigated area. A dry spell of 30 to 50 days without rain requires a corresponding reserve. Contact Promax for help with capacity calculations.

  • 10,000 litre water tank: for a large household or small farm. Suitable as a primary source or as buffer storage when connected to mains.
  • 15,000L: a mid-range capacity, available in the XPRESS series. For a lifestyle block or farm where 10,000L is not enough.
  • 25,000 litre water tank: for a large farm or commercial site. A substantial reserve for independent use.
  • 30,000L: the largest tank (big water tank) in the Promax range. For large farming operations, wineries, and industrial sites.

If one tank is not enough, multiple tanks can be connected in parallel using a Tank Balancing Kit. The water level equalises automatically between connected tanks.

ENDURO Series: 10,000L to 30,000L

Corrugated walls provide increased structural rigidity. Round poly water tank, vertical installation.

Capacities: 10,000L, 25,000L, 30,000L.

Colour options vary by capacity:

  • 10,000L: 7 colours
  • 25,000L: 7 colours
  • 30,000L: Monument Grey, Black

ENDURO large tanks are available on the North Island (Kerikeri factory).

ENDURO tanks 10,000L and above can be partially buried up to 1 metre without voiding the warranty. This reduces the visible height and simplifies connection to gravity-fed systems.

Warranty: 20 years, pro-rata.

XPRESS Series: 10,000L to 30,000L

Smooth walls simplify installation of level indicators, pumping equipment, and fittings. Round tank, vertical installation.

Capacities: 10,000L, 15,000L, 25,000L, 30,000L.

XPRESS offers a wider range of capacities in this category, including 15,000L, which is not available in the ENDURO series.

Colours: 2 colours. 30,000L available in 1 colour.

Availability by island:

  • 10,000L: South Island only
  • 15,000L, 25,000L: both islands
  • 30,000L: North Island (contact Promax to confirm)

XPRESS tanks can be set into a depression but cannot be backfilled. Backfilling voids the warranty. For partial burial with backfill, Promax recommends the ENDURO series. For full underground installation, see the separate Underground Tanks range.

Warranty: 20 years, pro-rata.