Maintaining your rainwater tank

Rainwater tank how to's

It's important to remember that your rainwater tank requires regular maintenance to do its job. But it doesn't take much to get up to speed. We've put together 3 simple ways to check your rainwater system is working, plus some mini tutorials on how to keep it clean and reliable. If you haven't installed your rainwater tank yet, check out rainwater tanks.

How to check the system is working

Is there rainwater in the tank?
Look inside the tank or knock on the side and listen for sounds of water. The water level may be low if there hasn't been much recent rain.

Are your pump and mains switching device plugged in and turned on?
If your rainwater system uses a pump, you'll find it on the inside or the outside of your tank. Check that the connections are on.

Are you using rainwater?
Turn on a tap, flush a toilet or turn on your washing machine – whatever should be connected to your tank. You should hear the sound of your pump starting up. If you have a gravity-fed system, just check that the water is flowing.

How to maintain your rainwater system

We've summarised what you need to watch out for. Plus we've put together some mini maintenance tutorials so you'll know how to keep your rainwater system in great condition from tank to tap.

Your gutter, screens and downpipes are key components of your rainwater system. They divert water from your roof into your tank and are commonly overlooked when it comes to maintenance. Simple ways to prevent blockages and improve the water quality of your system include:

  • trimming back overhanging vegetation
  • regularly checking and cleaning your gutters
  • removing leaves and debris from your roof's catchment area
  • clearing your screens and downpipes
  • installing a good quality gutter guard and downpipe screen.

When it starts to rain, the rain will wash debris, dirt and leaf litter from your roof and gutters into your rainwater system. A first flush device diverts the first flow of dirty rainwater to a separate chamber, stopping it from entering your tank. This chamber will slowly empty the dirty water through a small restrictor that can block easily. We recommend cleaning your first flush and flow restrictor every 3 to 6 months, or after each heavy rainfall event, to make sure that the chamber is empty and clear of blockages.

Not all systems have a first flush device. If you're not sure what to look for, watch the video below.

How to clean your first flush device
  1. Unscrew the bottom of the first flush device. Take care to avoid being splashed by dirty water as it rushes out.
  2. Rinse out the bottom cap that you unscrewed (and all its components) with fresh water.
  3. Reassemble everything as you found it.

A tank inlet screen stops leaves, debris and mosquitos from entering your rainwater tank. Make sure you clean them regularly. If your screen is screwed in, you can buy a removable tank screen that fits on top of your tank and is easy to clean.

Check if you need a filter on the outlet of your tank. If so, we recommend checking and maintaining your filter monthly until you're able to determine how often this needs to be done for your system. Follow the manufacturer's instructions to clear or replace the filter.

A mains switch detects the water level in your tank. If the tank is low or empty, or if your pump has stopped, it will switch to the mains drinking water supply.

You need to regularly check your mains switching device and pump to make sure they're working as they should. Sometimes they can fail after an electrical storm or blackout and will need to be reset manually. Check your owner's manual or manufacturer's instructions so you can identify when your system has failed.

Not all systems have a pump and mains switching device. If you're not sure what to look for, watch the video.

How to drain your rainwater tank

If you need to drain your rainwater tank, check what to do with your local council first. They'll let you know what you need to do. Here's why:

  • Your LGA may have rules about draining rainwater tanks.
  • There may be restrictions if your stored rainwater has been treated.
  • The configuration of your plumbing may cause issues – for example, some water tanks are topped up with drinking water from our mains.

How to sort out a problem

Contact a rainwater system specialist or request a WaterFix® Residential appointment. Our WaterFix Residential plumbers can check that your system is working correctly. They'll provide a quote to repair any issue. Have this information handy when you contact us:

  • What problems have you experienced with your system?
  • How often do you hear your pump running?
  • When was your system last cleaned, if at all?
  • What's your system connected to – toilets? garden taps? irrigation? washing machine?
  • When was your tank installed?
  • What size is your tank?