How much do you know about your hot water anode? If the answer is “almost nothing,” don’t feel bad, because most homeowners are in the same boat as you. But this small, inexpensive, hidden part inside your hot water system could be the key to preventing rust, smells, leaks – even premature tank failure.
It’s one of those things you don’t realise matters … until it does. And it’s too late.
In our guide, we’ll walk you through what an anode does, why it matters for your system’s health, and the warning signs that yours may need checking or replacing. Whether you’ve got an old electric unit or a newer gas model, these signs apply to almost every storage tank system out there.
So, what is an anode, anyway?
And what does an anode do? Every storage-style hot water system has a metal rod inside it – usually magnesium or aluminium – that’s designed to attract corrosion away from the steel tank. It’s called a sacrificial anode, because it literally sacrifices itself so your tank stays protected.
When the anode is in good condition, your tank stays clean inside. But when the rod is fully corroded, rust starts eating away at the tank walls – and you won’t know until the damage is done.
So how do you know yours may need a cheap replacement?:
1. Your hot water smells like metal or rotten eggs
Unpleasant smells are one of the most common early warning signs.
That rotten egg smell (especially in rarely used taps or showers) is often caused by bacteria reacting with the magnesium rod inside your tank.
It’s not dangerous – but it’s a sign the anode might be breaking down. A smelly tank doesn’t always need replacing – but you could be just a few steps shy of a failed system. So a check by a licensed plumber to make sure the problem isn’t corrosion or bacteria build-up is probably a very good idea.
2. Water has a rusty or brown tint
If your hot water has started to look brown or rusty, especially first thing in the morning, this could point to an aging anode hot water system.
The discolouration usually comes from sediment or early-stage corrosion forming inside the tank. When caught early, an anode rod replacement can fix the issue and extend the life of your system.
Wait too long, though, and you might need a whole new tank.
3. You hear rumbling or popping noises
Strange sounds from your tank (like rumbling, banging or popping) are usually caused by sediment buildup on the bottom of the tank – which is often a sign the sacrificial anode hot water system component has broken down and isn’t doing its job anymore.
This can lead to overheating, inefficiency, and stress on the internal components.
4. Your system is more than 5 years old
Even if everything seems fine, a system that’s over five years old should have its hot water system anode checked as part of routine servicing. Some systems will last longer – but many Australian tanks begin to degrade internally around the 5-7 year mark if the anode hasn’t been touched.
Here at Fix-It Right Plumbing, we include anode for hot water system inspection in our standard system servicing across Melbourne, Geelong, Canberra and beyond.
5. You’re going through heaters more often than you should
If you’ve had to replace your hot water tank sooner than expected, it’s worth checking whether the anodes for hot water systems were ever serviced. Often, a perfectly good tank is lost to rust simply because the anode was never inspected – or replaced.
Regular checks could save you thousands over time.
6. There’s water pooling at the top of the tank
Hot water heater leaking from top anode? In other words, do you see water around the top of your system? It could be a valve issue … or it could be a failing anode. Specifically, the thread or seal where the rod is inserted may be compromised, allowing water to seep.
If left unchecked, this slow leak can turn into full-blown rust damage. Our plumbers can assess whether it’s time for a sacrificial anode water heater replacement or just a simple tightening or reseal.
7. You’ve never heard of an anode before now
If this blog is your first intro to the concept of hot water system anode replacement, there’s a good chance yours has never been checked. And if your system is more than a few years old, that could mean trouble down the track.
Replacing an anode is much cheaper than replacing an entire tank – and if your tank is still in good shape, we can often put a new rod in place in under an hour.
What happens during a hot water anode replacement?
Here’s how we handle it at Fix-It Right Plumbing:
- We isolate the system and relieve pressure.
- The old hot water tank anode is removed (sometimes with a bit of effort if it’s corroded solid).
- We inspect the condition of the rod and internal tank.
- If appropriate, we install a new HWS anode (aluminium or magnesium depending on system type and water quality).
- The tank is resealed and tested.
It’s clean, fast, and gives you peace of mind that your system isn’t quietly rusting from the inside out.
How often should you replace the anode?
Generally every 3 to 5 years – but it depends on:
- The quality of your water (hard water means faster corrosion)
- The tank size and hot water brand
- Whether your system is under heavy demand
We recommend having the anode inspected every 2-3 years once your system passes the 5-year mark – especially if it’s in daily use by a family.
A cheap & tiny part that saves big money
Don’t wait for your tank to fail before looking into your anode. Like all good maintenance, it’s the simple stuff that protects you from major costs later on.
At Fix-It Right Plumbing, our friendly team is always just here to help with quick, honest advice on anode servicing and system health – whether your tank is brand new or 10 years old and making weird noises.
Book your anode check today
Think your system might be due? Call Fix-It Right Plumbing and ask about our hot water anode inspections and replacements. We offer professional hot water servicing in Melbourne, including full system checks and anode replacements, reliable hot water inspections in Geelong, and expert hot water system maintenance in Canberra. You’ll get honest advice – no pressure, no upselling – just the peace of mind that your system is being properly looked after.
Give us a call or book online now.
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