How to

Above Ground Tank Installations & Maintenance

Choose a tank

How to calculate what size tank would be sufficient for Rainwater Harvesting:

Roof p/m² Tank Size
50 – 100 1000 L - 2000 L
200 - 400 2500 L - 10 000 L

The biggest downfall of Rainwater Harvesting is lack of storage capacity.

Tank placement

Should preferably be at a downpipe, or alternatively be repositioned by use of proper piping/guttering.

Base / foundation

Tanks must be installed on a sound, level and smooth surface. Level paving will suffice, or a properly designed tank stand, alternatively a concrete plinth needs to be built. Ideally the plinth should be covered by a concrete topping at least 85mm thick.

Recommended minimum base sizes are as follows:

Tank (Volume) Tank Diameter Base Diameter
1000L(Slim) 850mm 950mm
1500L (Slim) 910mm 1010mm
2000L 1520mm 1620mm
Tank (Volume) Tank Diameter Base Diameter
2500L 1520mm 1620mm
5000L 1920mm 2020mm
10 000L 2300mm 2400mm

1. Base / concrete plinth

Tip: Make sure the concrete is cured before placing the tank on the slab and remember that the base must not be undermined by overflow water (85mm slab height)

Ensure tank is installed on a suitable base. The base must be sound, level, smooth, free of any protrusions and at least 100mm wider than the base of the tank (refer to pre-installation).

2. Select pre-filtration

Select desired pre-filtration options.Pre-filtration will differ depending on preference and what the water will be used for.

Pre-filtration options to choose from:

A Mesh/Tank Screen (fitted beneath lid, helps keep out smaller debris, insects etc)
B Rainhead/Leaf eater (removes larger debris)
C Fish Flush Diverter(takes off initial dirty water)

3. Tank screen (optional) and leaf eater (recommended)

A Ensure the tank screen is fitted beneath the lid of the tank.
B Fit the leaf eater to the downpipe (vertically or horizontally).

4. First flush diverter (optional)

Install the first flush diverter as per instructions provided inside packaging.
Note: the first flush utilizes a dependable ball & seal system, requiring no manual intervention.

5. Cut a hole in the tank lid or roof of the tank

Cut a hole of 110.5mm in the middle of the lid and fit the pipe through the hole, stopping before the mesh/tank screen.