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GRAF Carat-XXL Rainwater Tank.
  • GRAF Carat-XXL Rainwater Tank.
  • GRAF Carat-XXL Garden-Comfort Rainwater Harvesting Package.
  • GRAF Carat Garden-Comfort Rainwater Harvesting System.

16,000 litre GRAF Carat XXL Garden-Comfort Rainwater Harvesting System

10-14 working days
10-14 working days
£6,038.54 ex. VAT

Product Details

This item is supplied to order and additional refund & returns terms apply.


Tank Type: Large Capacity
Capacity: 16,000 litres
Length: 4660mm
Width: 2500mm
Height: 3160mm
Inner Ø dome shaft: 650mm
Tank Weight: 805kg
Dome Shaft Weight: 9kg (pedestrian loading)/55kg (vehicle loading)
Warranty: 15 Years

This 16,000 litre Carat XXL Garden-Comfort Rainwater Harvesting system from GRAF is designed to be a simple garden solution that uses a submersible pump to supply filtered rainwater for use in garden irrigation, car washing and general outdoor cleaning.

Product Features at a Glance:

  • Simple to install and use
  • Large capacity tank
  • Use a simple hose connection socket and pressure sensitive pump for automatic water activation
  • Low visual impact
  • Reduces electricity consumption by using a pressure drop activation system, so that electricity is only used when required
  • Integrated filter technology (100 % water yield)

Customer Notice: The processed water may be used to water the garden, flush toilets, wash clothes and as conventional cleaning water. It is Not suitable for consumption or personal hygiene.

GRAF garden packages have a basket filter that reliably holds back contaminants, whilst the filter construction guarantees a water yield of 100%. The tank's dome shaft provides easy access to the filter and tank, and comes with a cover suitable for either pedestrian loading or vehicle loading that blends seamlessly into the ground surface. It also features a submersible pump that switches on and off automatically.

The complete package includes:

1 x Carat XXL underground tank
1 x Maxi tank dome with connection DN 150
1 x Mini telescopic dome shaft with PP cover (pedestrian loading)
 or Cast iron telescopic dome shaft with childproof cover (vehicle loading up to 3.5 ton)
1 x Garden XL Filter package consisting of:

    • XL Internal Universal Filter 3
    • Calmed Inlet
    • Inflow stilling system for controlling the water inflow
    • Overflow siphon and rodent guard
    • Spannfix pipe connection sleeve

1 x Garden Comfort Pump Package:

    • Integra INOX Submersible and suction pump
    • Floating water extraction unit
    • PE pressure max. 10 m (32' 10")
    • Water hose connection box internal and external

The rainwater stored in the tank can be extracted very easily. The unique water hose connection box allows you to connect up equipment for watering the garden, and can be installed at any location in the garden or in the tank cover itself - just simply connect your garden hose or lawn sprinkler to the integrated standard connection valve.

The Carat tank series are the foundations of a long-lasting rainwater harvesting system. Manufactured by injection compression moulding, these tanks boast unbeatable stability with each component produced to the highest accuracy. The tank dome can be rotated 360° and sits on a telescopic, inclinable shaft allowing it to be easily aligned to connection pipes and installed flush with the soil level. Add to that its intelligent filter components and you have an easy to install system that ensures the best quality from your harvested rainwater. 

For more information about rainwater harvesting, and advice on how to choose a system and tank size, take a look at our supporting articles here.

Key Features of Carat Garden Comfort Tanks:

  • 100 % water yield - GRAF garden packages have a basket filter that reliably holds back contaminants and guarantees a water yield of 100 %.
  • Dome shaft - provides easy access to the filter and tank, can be fitted with covers suitable for either pedestrian or vehicle loading.
  • Automatic pump - the Carat Garden-Comfort package includes a submersible pump that switches on and off automatically, supplying on demand water easily to the tap.
  • Easy extraction - GRAF's unique water hose connection can be installed at any location in the garden, or in the tank cover itself, providing easy access for all your garden equipment.
  • Versatile Tank Cover - can be telescoped and tilted in a continuously variable manner and blends seamlessly into the ground surface.
  • Suitable for Vehicle Loading - when combined with a cast iron telescopic dome shaft, meaning the Carat tank can then be installed under your driveway.


Please Note: All dimensions are approximate (the manufacturer reserve a tolerance of +/- 3%) and the useful volume of the tanks may be up to 10% lower than the tank capacity, according to the connecting option. All images shown are used for illustration purposes only and may differ from the actual product supplied.

Disclaimer: Pre-condition for warranty benefits are proper handling, assembly and installation according to the mounting guidelines. The warranty may become invalid if any of these conditions are breached.

10-14 working days
Install Type:
Below Ground
Product Type:
Large Capacity
11,000 - 20,000 litres