Rain Harvesting Accessories Rain Harvesting Accessories

Rain Harvesting Accessories

Promax rain harvesting accessories support every stage of the system, from roof filtration through to water delivery into the house. The range includes filtration, first flush, tank cleaning, pump, treatment, connection, and control components to help build a complete rainwater harvesting system.

The right accessories help improve water quality, protect pumps and plumbing, and make a rainwater system easier to install, monitor, and maintain. For tanks, see the Small Water Tanks, Large Water Tanks, or Slimline Water Tanks collections.

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Brass Ball Valve - 100mm

Brass Ball Valve - 100mm

$914.00
$914.00
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How a Rainwater Harvesting System Works

A rainwater harvesting system works in four main stages: collection, storage, treatment, and delivery. Rain falls onto the roof, travels through gutters and downpipes, and passes through inlet filtration before entering the tank. From there, water is stored until it is needed, then drawn out through the outlet side of the system for treatment and use around the property.

The quality and performance of the overall system depend on how well these stages work together. Good accessories help reduce debris entering the tank, limit sediment build-up, protect pump performance, and improve the quality of water being delivered for irrigation, toilet flushing, laundry, or other approved uses.

Why the Right Accessories Matter

A water tank on its own stores water, but the accessories are what turn it into a reliable rain harvesting system. The right setup helps manage leaves, roof contaminants, sediment, water level, pressure, and water treatment, while also making the installation safer and easier to maintain over time.

This is especially important where rainwater is being reused around the home. Better filtration and system design can improve water quality, reduce wear on pumps and fittings, and support more consistent performance through changing weather conditions. A well-planned system is not just about collecting water, it is about making that water more usable.

Pre-Filtration Before Water Enters the Tank

The first step in protecting water quality is stopping debris before it reaches the tank. Pre-filtration accessories are designed to screen out leaves, insects, and larger contaminants at the downpipe, helping keep stored water cleaner from the start. This reduces the amount of organic matter entering the tank and helps lower the risk of sludge, odour, and maintenance issues later on.

First flush devices are also an important part of best practice. They divert the initial roof runoff at the start of a rain event, which is often the dirtiest water and may contain dust, pollen, bird droppings, and other roof contaminants. Together, inlet filtration and first flush management help improve water quality before the water even reaches storage.

Keeping Stored Water Cleaner Inside the Tank

Once water is inside the tank, the goal is to protect the cleanest part of the stored supply and reduce sediment problems over time. Accessories that support in-tank water quality can help remove settled material, improve the point where water is drawn from, and make it easier to monitor how much water is available.

This matters because water quality can vary within the tank itself. Sediment tends to collect at the bottom, while floating matter can gather at the surface. A well-designed outlet setup helps draw water from the cleaner zone in between. Monitoring tools also make it easier to manage supply, avoid pump run-dry issues, and keep the system operating efficiently.

Pumps, Filtration, and Water Delivery

To use stored rainwater effectively, the system needs to move water where it is needed and, where required, treat it before use. Pump and delivery accessories help supply water for irrigation, washdown, toilet flushing, laundry, and other applications depending on the design of the system. For some setups, automatic changeover between tank water and mains supply may also be part of the solution.

Where higher water quality is required, outlet-side filtration and treatment become increasingly important. Sediment filters, carbon filters, and UV treatment can all play a role depending on the intended use. These components help improve water clarity, reduce taste and odour issues, and support safer household reuse where the system has been properly designed.

Fittings, Valves, and System Expansion

A rainwater system also depends on the smaller connection components that make the full setup work properly. Fittings, seals, valves, outlets, inspection points, and connection kits all help join the tank to pipework, overflow, pumps, and other accessories. Choosing the right parts improves reliability, simplifies installation, and helps create a cleaner, more serviceable system.

These components also make it easier to adapt the system over time. A tank setup may begin as a simple garden water solution and later expand to include pump supply, additional filtration, or connection between multiple tanks. Good system design allows that flexibility, making it easier to increase capacity, improve performance, or tailor the setup as the needs of the property change.