5 % discount on the price of your tank. Offer valid from 1 May 2024 to 30 June 2024

šŸ“Œ Please note that the 5% discount is applicable to the tank price only and does not apply to installation, transport, or fittings.


NO CONCRETE WORKS ARE REQUIRED for Oasis Tanks under 350,000 litres. Tanks in excess of 350,000 litres require only a simple concrete ring beam upon which the tank is installed.

Oasis Tanks

are installed directly onto the ground, onto a levelled sand pad. Proper and careful preparation of the site and sand pad is essential to ensure long and trouble-free service from your Oasis tank in years to come. This is a simple exercise that can be easily undertaken either by you or by an accredited Oasis Tanks installer.

1. Site

Select a site on flat, level ground that is stable. Where possible, position the tank on natural (undisturbed) ground, rather than on reconstituted (disturbed) ground or earth-fill.

2. Excavate

Excavate the site:

  • 2m WIDERĀ than the tank diameterĀ 
  • to aĀ depth of 150mm
  • ensuring that the excavated area isĀ flat and level.

3. Remove

Remove all sharp rocks, debris or roots. Where necessary, take action to prevent root re-growth or termitarium growth.

NOTE. When fill-material has been used to level the site:

  • provide adequate retaining walls to stabilise the tank site
  • compact the site to a minimum of 50kPa.

4. Drainage

Provide sufficient drainage:

  • to divert water from the tank site after heavy rainĀ 
  • to prevent erosion of the sand pad due to run-off from the tank roof, or from adjacent, elevated areas.Ā 

Sand Pad Instalation


The sand pad forms the protective layer upon which the liner rests. Sand pad material should be free-draining, sieved pit or plaster sand, and free of sharp objects or debris.Ā 

Order the required amounts of sand pad material AND 19mm aggregate for delivery on site (see calculations below).

  • Fill the levelled, excavated site with sand pad material to a depth of 150mm, lightly compact and ENSURE THAT THE PREPARED SITE IS DEAD LEVEL (approximately 10mm tolerance) and free of any objects capable of causing damage to the liner.


In the event that a contractor is required to perform the site preparation, position the required volume of sand pad materialĀ directly adjacent to the tank’s proposed installation site.

On Installation Day

  1. If using an accredited Oasis Tanks installer, please be present to point out your preferred positions for the tank fittings (if prior arrangement has not already been made in this regard).
  2. NOTE: IT IS IMPERATIVE THAT THE TANK IS IMMEDIATELY FILLED to a minimum of 10% of its volume in order to correctly seat the liner against the tank walls. Failure to fill the tank immediately will void the Oasis Tanks Warranty.

After Installation

Install a bed of 19mm crushed rock aggregate, 1000mm wide x 100mm thick, around the entire circumference of the tank on the exposed sand pad, to protect the sand pad material from wind or water erosion.

NOTE: Please arrange for the aggregate to be delivered to siteĀ at the same timeĀ as the sand pad material. This will enable the protective aggregate bed to be installedĀ immediatelyĀ after the tank installation has been completed.Ā 


The Oasis Tanks Product Warranty is subject to the site preparation being performed strictly in accordance with the instructions provided above.

How to calculate the volume of 19mm aggregate (1000mm x 100mm) required:

EXAMPLE: the volume of sand required for aggregate around a 6.6m diameter tank:Ā 

A. Calculate the tank footprint area i.e. 6.6m diam. (pi x rĀ²) 3.14159 x 3.3 x 3.3 = 34.2mĀ²

B. Calculate the area of the sand pad footprint i.e. 8.6m diam. 3.14159 x 4.3 x 4.3 = 58.0mĀ²

C. C = Area of the aggregate footprint: B minus A = C 58mĀ² – 34.2mĀ² = 23.8mĀ²

D. Volume (100mm deep) aggregate required: C x 0.1m 23.8mĀ² x 0.1m = 2.38mĀ³ (order 2.5mĀ³)

Order 2.5mĀ³ (rounded off) of aggregate

How to calculate the volume of sand required:

  1. EXAMPLE: the volume of sand required for the sand pad of a 6.6m diameter tank:

    Diameter: 6.6m + 2m = 8.6m See 2.a. above

    Radius (r): 8.6m/2 = 4.3m

    Depth of sand: 150mm (0.150m) See 2.b. above

    Volume (mĀ³) sand requiredĀ = pi (3,14159) x (radius of sand pad)Ā² x depth of sand (m)

    3.14159 x (4.3 x 4.3) x 0.150m = 8.7mĀ 

    Order 9mĀ³ (rounded off) of sand