Capacity guide

30,000 litre water tank

The largest single-tank class in this calculator, for high storage needs or fewer units in a linked system.

30 kL tank, reaching about 0% full at its lowest point over an average year A corrugated cylindrical rainwater tank. Blue water shows the lowest modelled level, with a small shaded band at the base for water below the usable outlet.

Illustrative tank shape. Water level depends on your calculation.

Capacity
30,000 L

What to consider

  • Capacity alone does not establish suitability. Calculate against daily demand, connected roof area, local rainfall and the dry-period reserve.
  • This is nominal capacity. Confirm usable volume, outlet height, fittings and pump setup for the selected product.
  • Check the manufacturer’s base, access, clearance and installation requirements before ordering.
  • Confirm delivery access for a large tank, including gateways, turning space and overhead obstructions.
  • Any required firefighting reserve is separate from the household water you plan to use; confirm local requirements.

Capacity sources

This generic sizing ladder was checked against current New Zealand ranges from:

Availability, dimensions and usable volume vary by product. Confirm the actual specification before buying.

Will this capacity work for your home?

Calculate against your household use, connected roof area and local rainfall.

Calculate your tank size