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GRAF Carat-S Garden Rainwater Harvesting System 2700L | G70075

£1,745.00
£2,094.00 (inc VAT)
£1,745.00 (exc VAT)

FREE UK 
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Product Description

This product is delivered directly from the supplier, lead times vary.

 

The GRAF Carat-S Garden Comfort Complete Package 2700L is a complete underground rainwater harvesting system designed to provide a reliable and sustainable water supply for garden irrigation and outdoor cleaning. With a 2,700-litre underground storage tank, this package allows you to collect, store and reuse rainwater, helping to reduce mains water consumption by up to 50% while lowering water bills and supporting environmentally responsible water use.

Built around the durable GRAF Carat-S tank, this system combines long-lasting performance with simple installation. The patented quick-connect design enables rapid assembly without screws, while the integrated filtration components help maintain water quality for a dependable supply of harvested rainwater. Ideal for watering gardens, washing vehicles, cleaning patios and other outdoor tasks, this complete package delivers an efficient, low-maintenance rainwater harvesting solution.

 

Key Features & Benefits:

  • Complete 2,700-litre rainwater harvesting system
  • Ideal for garden irrigation and outdoor water applications
  • Helps reduce mains water consumption by up to 50%
  • Durable underground tank with a 50-year design life
  • Patented quick-connect assembly system with no screws required
  • Suitable for granular backfill in appropriate ground conditions
  • Internal and external hose connection points for convenient water access
  • High-performance basket filter helps remove leaves and debris
  • Inflow stilling system improves water quality within the tank
  • Overflow siphon included as standard
  • Pedestrian and vehicle-loading cover options available
  • EPDM seals tested for over 25 years of performance
  • Environmentally friendly and cost-effective water-saving solution
  • Low-maintenance design with reliable year-round operation

 

What's Included

  • Carat-S 2700L underground rainwater tank
  • Telescopic Dome Shaft Mini Green with PE lid
  • Carat basket filter
  • Inflow stilling system
  • Overflow siphon
  • Spannfix DN100 connector
  • 25m roll of 25mm rainwater harvesting pipe with fittings
  • Internal hose connection box
  • External hose connection box

 

Specification Value
Maximum Capacity 2,700 Litres
Dimensions (L × W × H) 2080 × 1565 × 1400 mm
Weight (Empty) 120 kg
Tank Design Life 50 Years
Tank Warranty 15 Years



Graf Technical Set Garden Submerge

Graf UNIVERSAL-FILTER 3 Intern

Graf Carat Installation Manual

 

SKU: TANRAINGRA011

Why Choose Direct Drainage for Rainwater Harvesting?

Free Tank Delivery

Tanks ship direct from the manufacturer, with lead times varying by product.

Best Price Guarantee 

Found the same tank cheaper? Send us the quote and we’ll try to match it.

Sustainable Water Solutions

Collect, store and reuse rainwater for irrigation, domestic and commercial applications.

Expert Tank Support

Need help choosing the right tank? Call our team on 01388 537050.

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CUSTOMER REVIEWS

Rated 4.8/5 by Direct Drainage Customers

Based on over 600 verified reviews

VERIFIED REVIEW

Very helpful from the start to the finish

Items were despatched quickly and arrived the next day. Would recommend.

Title

North Hayne Farm Cottages | 26 June 2026

VERIFIED REVIEW

Cheapest price I could find for the pump

Cheapest price I could find for the pump and delivery the next day what more could you want.

Title

Sam Jukes | 5 November 2025

VERIFIED REVIEW

Great service!

I ordered a septic tank it was delivered within a week and the delivery driver left it in the exact right place and time. Would definitely use this company again, thanks so much.

Title

Eve Harland | December 2025

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FAQs

Everything you need to know about rainwater harvesting systems, water storage tanks and sustainable water reuse.

What is a rainwater harvesting system, and how does it work?

A rainwater harvesting system collects and stores rainwater, typically from building roofs, for reuse in suitable non-drinking water applications.

 

Rainwater is directed through gutters and downpipes into a storage tank, often passing through a filter to remove leaves, debris and other contaminants.

 

Depending on the system, the collected water can then be supplied to garden irrigation systems, toilets, washing machines or other suitable applications.

 

Our range includes complete rainwater harvesting systems, underground storage tanks and accessories for domestic, commercial and agricultural use.

What can harvested rainwater be used for?

Harvested rainwater can be used for a variety of non-potable applications, helping reduce reliance on mains water.

 

Common uses include:

  • Garden watering and landscape irrigation.
  • Toilet and urinal flushing.
  • Vehicle washing and outdoor cleaning.
  • Agricultural irrigation.
  • Washing machines, where supported by a suitable system.
  • Certain commercial and industrial applications.

The intended use will determine the type of rainwater harvesting system, filtration and pumping equipment required.

 

Harvested rainwater should not be used for drinking or food preparation without appropriate treatment and verification of water quality.

What size rainwater harvesting tank do I need?

The correct rainwater harvesting tank capacity depends on your property's roof area, local rainfall levels, available installation space and expected water consumption.

 

For example, a system used exclusively for garden irrigation may require a different storage capacity from one supplying toilets and washing machines throughout a property.

 

Our range includes smaller rainwater storage tanks alongside larger-capacity systems for domestic, commercial and agricultural applications.

 

When choosing a tank, it's important to consider both the amount of rainwater you can collect and how much you expect to use.

 

If you're unsure which capacity is suitable, our team can help you identify an appropriate product.

What is the difference between an above-ground and underground rainwater harvesting tank?

Above-ground and underground rainwater harvesting tanks provide different storage solutions depending on your available space and installation requirements.

 

Above-ground tanks are typically easier to access and are commonly used for garden watering, irrigation and general outdoor water storage.

 

Underground tanks are installed below ground level, allowing larger quantities of rainwater to be stored without occupying valuable surface space.

 

Underground systems are particularly popular for new-build properties, landscaping projects and complete domestic rainwater harvesting installations.

 

The best option depends on your required capacity, available space, intended use and installation conditions.

Can rainwater harvesting systems reduce my water bills?

Yes. Rainwater harvesting systems can help reduce mains water consumption by collecting and reusing rainfall for suitable non-potable applications.

 

Using harvested rainwater for activities such as toilet flushing, garden irrigation and vehicle washing can reduce the amount of treated mains water required.

 

However, actual savings depend on rainfall, storage capacity, water usage, system efficiency and whether your property has metered water charges.

 

Some systems also require electricity for pumps and regular maintenance.

 

Choosing an appropriately sized system is important for achieving practical long-term water savings.

Do rainwater harvesting systems require maintenance?

Yes. Regular maintenance helps ensure rainwater harvesting systems continue operating efficiently and reliably.

 

Maintenance may include inspecting and cleaning filters, removing accumulated debris, checking pumps and inspecting tank connections.

 

Underground and above-ground systems may have different maintenance requirements depending on their design and components.

 

The frequency of maintenance depends on the system, surrounding environment and amount of debris entering the collection area.

 

Always follow the manufacturer's maintenance instructions to help maintain water quality and reliable system operation.

How much is delivery, and when will my rainwater harvesting system arrive?

Many of our rainwater harvesting tanks and systems are supplied directly from the manufacturer, with delivery lead times varying depending on the product and availability.

 

Free delivery is available on eligible products to most mainland UK postcodes, although additional charges or restrictions may apply.

 

Larger tanks and systems may require specialist transport, suitable delivery access and appropriate offloading equipment.

 

For current availability, delivery information or an estimated lead time, please contact our team on 01388 537050.