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Klargester AquaHarvest Direct Rainwater Harvesting System 4600L

£3,185.00
£3,822.00 (inc VAT)
£3,185.00 (exc VAT)

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Product Description

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

 

Reduce water bills, lower mains water consumption, and make your home more environmentally friendly with the Klargester AquaHarvest 4600L Direct Rainwater Harvesting System. Designed specifically for domestic properties, this advanced rainwater harvesting system captures, stores and reuses rainwater for a range of everyday non-potable applications, helping homeowners maximise water efficiency without compromising performance.

The AquaHarvest Direct System is the ideal solution for homes where a traditional header tank is not practical, such as properties with converted loft spaces or limited attic storage. Instead of relying on gravity-fed distribution, the system uses an intelligent Grundfos pressure pump to deliver filtered rainwater directly from the underground storage tank to appliances at mains pressure or higher.

 

Why Choose the Klargester AquaHarvest 4600L?

With a generous 4,600-litre capacity, the AquaHarvest provides an efficient and sustainable way to reduce reliance on mains water. By harvesting naturally occurring rainfall, homeowners can significantly cut annual water usage while reducing their environmental impact.

The system is fully compliant with EN 16941-1:2018 Rainwater Harvesting Standards, providing complete peace of mind that your installation meets the latest industry requirements.

 

Key Features & Benefits

  • 4,600 litre underground rainwater harvesting tank
  • Direct-feed system with no header tank required
  • Ideal for homes with converted lofts or limited roof space
  • Fully compliant with EN 16941-1:2018
  • Intelligent Grundfos pump for reliable performance
  • Supplies water at mains pressure or higher
  • Suitable for shallow excavation installations
  • Easy-to-use control panel with water level monitoring
  • Early fault warning and system status indicators
  • Automatic mains water backup during dry periods
  • Calmed inlet design helps maintain optimum water quality
  • Low-maintenance, energy-efficient operation

 

Suitable Uses for Harvested Rainwater

The AquaHarvest system supplies filtered rainwater for a variety of domestic applications, including:

  • Toilet and WC flushing
  • Urinal flushing
  • Garden watering
  • Irrigation and landscaping
  • Vehicle washing
  • Domestic laundry

By using harvested rainwater instead of treated mains water for these applications, households can make substantial savings over time.

 

Save Water, Save Money

A typical four-bedroom home uses approximately 222 litres of water every day, with around 30% used for toilet flushing and a further 7% used outdoors. By replacing mains water with harvested rainwater for these non-potable uses, the Klargester AquaHarvest 4600L can help save up to 30,000 litres of mains water per year, helping to reduce household water bills while conserving valuable resources.

 

How the AquaHarvest Rainwater Harvesting System Works

Rainwater collected from the roof is channelled into the AquaHarvest system where it undergoes multiple stages of filtration before use:

  1. Rainwater passes through an inline leaf filter to remove larger debris.
  2. Additional filtration is provided at the pump inlet.
  3. Fine filtration ensures clean water delivery throughout the system.
  4. The intelligent Grundfos pump automatically activates whenever water demand is detected.
  5. During prolonged dry weather, an automatic mains water top-up prevents the system from running dry.

The result is a reliable, fully automated rainwater recycling system that delivers water efficiently whenever it's needed.

 

Ideal For

  • New build homes
  • Self-build projects
  • Eco-friendly housing developments
  • Sustainable residential properties
  • Homes seeking to reduce water bills and environmental impact

 

The Klargester AquaHarvest Domestic 4600L Direct Rainwater Harvesting System combines innovative pump technology, advanced filtration and dependable performance to provide a highly efficient solution for domestic rainwater reuse, helping homeowners save water, save money and support a more sustainable future.

 

Product Code Description
GRW080DKSW Rainwater 2350 Litres Direct (< 80m² Roof Area)
GRW110DKSW Rainwater 3100 Litres Direct (< 110m² Roof Area)
GRW160DKSW

Rainwater 4600 Litres Direct (< 160m² Roof Area)

 

Klargester AquaHarvest Domestic 4600L Installation Guidelines
Klargester AquaHarvest Domestic 4600L Drawing
Klargester AquaHarvest Specification

SKU: TANRAINKLA003

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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North Hayne Farm Cottages | 26 June 2026

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Cheapest price I could find for the pump

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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.