Why Your Toilet Keeps Running and How to Fix It
A running toilet is one of those household problems that’s easy to ignore until you see your water bill. That constant hissing or trickling sound coming from your bathroom isn’t just annoying, it’s a sign that your toilet is wasting water around the clock. In fact, a running toilet can waste anywhere between 200 to 400 litres of water every single day, quietly inflating your bills without a single visible drip on the floor.
The good news? Many cases of toilet repair that Rockingham homeowners face are entirely preventable and some can even be resolved with a few basic checks. This blog walks you through the most common causes of a running toilet, what you can do about it, and when it’s time to call in the professionals.
What Causes a Toilet to Keep Running?
Before jumping into toilet repair tips, it helps to understand what’s actually happening inside the cistern. Most running toilet problems come down to one of a handful of common faults.
1. A Faulty Flapper Valve
The flapper is the rubber seal at the bottom of your cistern that controls the flow of water into the bowl. Over time, flappers wear out, warp, or accumulate mineral deposits that prevent them from sealing properly. When the flapper doesn’t close completely, water continuously trickles from the cistern into the bowl which is exactly what causes that familiar running sound.
This is one of the most common causes of leaking toilets in Australian homes, and fortunately, it’s one of the more straightforward fixes.
2. An Incorrectly Adjusted Float
The float is the component that tells your cistern when to stop refilling after a flush. If the float is set too high, the water level rises above the overflow tube and drains continuously into the bowl. If it’s set too low, the cistern never fills properly and struggles to flush effectively.
Adjusting the float is one of the simpler toilet repair tips, many floats can be adjusted by hand or with a basic screwdriver but getting the water level right does require a careful eye.
3. A Worn Fill Valve
The fill valve controls how water enters the cistern after each flush. When this component wears out or becomes faulty, the cistern may refill slowly, noisily, or not at all. A hissing sound that persists long after flushing is a classic indicator of a failing fill valve.
4. A Damaged Overflow Tube
If the overflow tube, the vertical pipe inside your cistern is cracked or sitting at the wrong height, water will constantly drain away before the cistern can hold a full load. This leads to both a running toilet and poor flushing performance.
Simple Toilet Repair Tips to Try First
Before calling a plumber, there are a few things you can safely check yourself:
- Listen carefully: Is the running sound constant or intermittent? Constant running usually points to the flapper or float, intermittent running often suggests a slow leak.
- Check the flapper: Lift the cistern lid and press down on the flapper. If the running stops immediately, the flapper isn’t sealing properly and likely needs replacing.
- Add food dye to the cistern: Without flushing, add a few drops of food colouring to the cistern water. If colour appears in the bowl within 15 minutes, you have a confirmed leak between the cistern and bowl.
These checks can help you identify the fault but if you’re not confident working inside the cistern, or if the problem persists after basic adjustments, it’s always best to leave it to a licensed professional.
When to Call an Emergency Plumber Rockingham
Some toilet problems go beyond a quick DIY fix. You should call an emergency plumber that Rockingham residents rely on if you notice water pooling at the base of the toilet, the cistern is cracking or leaking externally, the flush mechanism has failed completely, or you’ve attempted a repair and the problem has returned.
Leaking toilets that are left unattended can cause water damage to your flooring, subfloor, and surrounding walls turning a minor repair into a major renovation.
The team at RDF Plumbing handles all types of toilet repair Rockingham residents need, from straightforward flapper replacements to complex cistern faults, with same-day service available across Rockingham, Kwinana, Mandurah, and the wider Peel Region.
Don’t Let a Running Toilet Drain Your Budget
A toilet that won’t stop running is never just a minor inconvenience, it’s a water and money leak that compounds every day you leave it unaddressed. Start with the basic checks outlined above, and if the problem persists, don’t hesitate to get a licensed plumber involved.
The sooner you address a running toilet, the sooner you stop paying for water you’re not actually using.
April 27, 2026