Picture this scenario: you've just moved into a new rental or inherited an older home, and when you lift the toilet lid, you're confronted with a ring of stubborn brown stains that look like they've been there since Federation.
Before you start ringing plumbers or shopping for a new toilet, there's a $13 solution that's quietly becoming legendary among Australian homeowners.
A professional cleaner's recent recommendation has sparked a cleaning revolution, with a humble Bunnings product saving households from spending hundreds on toilet replacements. The hero product? Scalex by Hillmark—a concentrated descaler that's turning even the most stubborn toilet stains into sparkling success stories.
In this article
The stains that stumped everyone
When faced with obstinate dark stained toilet bowls on which just about every cleaning method was tried to no avail, many Australian homeowners have felt completely defeated. Professional cleaner Jason Shipway from Enhanced Cleaning sees these challenging stains regularly in clients' homes.
'We see it all the time in new clients' homes,' Shipway explains. 'You'll typically only find it inside the toilet bowl, under the water line, because that's where the minerals in the water settle and harden over time.'
These aren't just surface stains that can be scrubbed away with elbow grease. The buildup involves calcium, lime and rust deposits that form what cleaning experts call 'calcification' - essentially creating a rock-like crust that regular household cleaners simply can't penetrate.
When everything else fails
The frustration is real for homeowners who've tried the usual suspects. One determined person tested most common recommendations: 'Coca-Cola—Zero result; dishwasher tab—zero, Polident—zero, citric acid—about 20 per cent (mostly just lightened it)' before discovering the game-changer.
'I tried bleach, stronger toilet cleaner and plain old scrubbing,' reports one mum of six, echoing the experience of countless Australians who've battled these stubborn stains. Even CLR (Calcium Lime Rust remover), often considered the heavy-duty option, frequently falls short against severe mineral buildup.
'My toilet had built up scum and was just horrible when I moved in 20 years ago. Tried everything even CLR, nothing worked till I found scalex, my toilet is like new.'
The $13 miracle worker
Enter Scalex—a highly concentrated formulation that removes calcium, lime and rust, ideal for removing scale from dishwashers, washing machines, laundry sinks, bathtubs, toilet bowls, drains, showerheads and tapware. Available at Bunnings for around $11-13, this unassuming powder has developed something of a cult following among cleaning enthusiasts.
Scalex is a heavy-duty home descaler by Hillmark that removes calcium, lime and rust. It can also be used to descale home appliances, clean white or pale-coloured tiles or grout—making it excellent value for households dealing with hard water issues throughout their home.
How to use Scalex for toilet cleaning
1. Empty as much water from the toilet bowl as possible using a plunger or old cup
2. Add 2 heaped teaspoons of Scalex powder directly to the bowl
3. Add warm (not boiling) water to cover the stained areas
4. Leave overnight or for at least 6-8 hours
5. Give a light scrub with the toilet brush and flush
6. For stubborn stains, repeat the process
Real results from real Australians
The testimonials are compelling. One user left Scalex Heavy Duty overnight and within 10 minutes the next morning, 'a quick scrub and stain was gone. Toilet looks brilliant'.
Another satisfied customer simply 'poured about 1 or 2 spoonfuls into the bowl and left it overnight. Quick scrub with the dunny brush in the morning and then flushed. Scale all gone! Job done'.
The transformation can be particularly dramatic for renters. 'Before anyone judges me no i am not a filthy person... I rent the property and the first pic is how the toilet was when i moved in i had tried everything', explains one user who successfully transformed her inherited toilet nightmare.
The cost-saving truth
Here's where this solution becomes particularly appealing for budget-conscious households. One woman even replaced her toilets over the issue, and with the average loo setting you back almost $500 spent hundreds more than the budget fix that a $13 product could have provided.
The financial comparison
- New toilet: $400-800 plus installation costs
- Professional cleaning service: $150-300
- Scalex solution: $11-13 (multiple uses)
- DIY pumice stone method: $5-10
- Toilet replacement due to stains: Completely unnecessary
For those on fixed incomes, this represents significant savings. The 375g container provides multiple applications, and many users report success on their first attempt.
Alternative approaches for the chemically cautious
For those who prefer chemical-free options, professional cleaner Shipway recommends the pumice stone method. 'The easiest chemical-free way to remove it is with a pumice stone; just gently scrub it away,' he suggests.
This approach requires more elbow grease but uses natural abrasion rather than chemical action. A pumice stone costs around $5-10 and can be reused multiple times, making it another budget-friendly option.
Source: @jason.cleans / Tiktok.
Safety considerations
Scalex contains sulfamic acid as the active ingredient in concentrated powder form, so proper handling is important. Always wear gloves when using the product, ensure good ventilation, and avoid contact with stainless steel cutlery or chrome surfaces as it may cause permanent tarnishing.
Never mix Scalex with other cleaning products, and store it safely away from children and pets. The concentrated nature that makes it so effective also means it requires respectful handling.
Did you know?
Did you know?
Australia's hard water areas, particularly in South Australia, parts of Victoria, and some Queensland regions, are more prone to mineral buildup in toilets. The calcium and magnesium in hard water create the perfect conditions for stubborn scale formation that regular cleaning can't prevent.
Prevention strategies for long-term success
Once you've conquered the existing stains, Shipway recommends regular maintenance to prevent future buildup. 'Using a descaler every few weeks can make a big difference,' he advises. This is particularly important in hard water areas.
Regular weekly cleaning with standard toilet cleaners, combined with monthly Scalex treatments, can keep mineral deposits from reaching the stubborn calcification stage. Consider it an investment in avoiding future cleaning nightmares.
Beyond the toilet bowl
The versatility of Scalex extends to dishwashers, washing machines, laundry sinks, bathtubs, drains, showerheads and tapware, making it excellent value for households dealing with mineral deposits throughout their plumbing.
One user reported: 'I originally purchased the scalex for cleaning my old toilet bowel and I worked a treat. I decided try a mixed solution on my shower screen, and it was brilliant. This product just made bathroom cleaning a lot easier'.
The cleaning revolution happening in Australian homes proves that sometimes the best solutions are the simplest ones. A $13 investment can save hundreds of dollars and transform what seemed like an impossible cleaning challenge into a overnight success story.
Before you consider drastic measures for stubborn toilet stains, give this Bunnings hero a try. Your wallet—and your toilet—will thank you for it.
What's your experience with stubborn toilet stains? Have you tried Scalex, or do you have other budget-friendly cleaning wins to share with fellow readers?
Primary Source
https://au.lifestyle.yahoo.com/prof...et-problem-see-it-all-the-time-190026738.html
Hillmark Scalex Heavy Duty Home Descaler 375g reviews | ProductReview.com.au
Cited text: Used in an obstinate dark stained toilet bowl on which just about every cleaning method was tried to no avail.
Excerpt: When faced with obstinate dark stained toilet bowls on which just about every cleaning method was tried to no avail
https://www.productreview.com.au/listings/hillmark-scalex
Hillmark Scalex Heavy Duty Home Descaler 375g reviews | ProductReview.com.au
Cited text: Used in an obstinate dark stained toilet bowl on which just about every cleaning method was tried to no avail.
Excerpt: When faced with obstinate dark stained toilet bowls on which just about every cleaning method was tried to no avail
https://www.productreview.com.au/listings/hillmark-scalex
Hillmark 375g Scalex Appliance Descaler—Bunnings Australia
Cited text: Scalex Heavy Duty is a highly concentrated formulation that removes calcium, lime and rust.
Excerpt: The buildup involves calcium, lime and rust deposits
https://www.bunnings.com.au/hillmark-375g-scalex-appliance-descaler_p4469185
Scalex by Hillmark from Bunnings: the best product to clean your black toilet stains | New Idea
Cited text: Coca-Cola—Zero result; dishwasher tab—zero, Polident—zero, citric acid—about 20 per cent. ( mostly just lightened it” ) And then I used the Scalex—OM...
Excerpt: One determined person tested most common recommendations: 'Coca-Cola—Zero result; dishwasher tab—zero, Polident—zero, citric acid—about 20 per cent (mostly just lightened it)'
https://www.newidea.com.au/food/bunnings-miracle-toliet-stains-hack/
'Amazing' $12 Bunnings product saves households hundreds
Cited text: The Scalex buy will only set you back $11-$12 at Bunnings or The Good Guys · “I tried bleach, stronger toilet cleaner and plain old scrubbing,” the mu...
Excerpt: 'I tried bleach, stronger toilet cleaner and plain old scrubbing,' reports one mum of six
https://au.lifestyle.yahoo.com/bunn...g-stain-remover-eleven-dollars-033010262.html
Hillmark 375g Scalex Appliance Descaler—Bunnings Australia
Cited text: Scalex Heavy Duty is a highly concentrated formulation that removes calcium, lime and rust. It’s ideal for removing scale from dishwashers, washing ma...
Excerpt: a highly concentrated formulation that removes calcium, lime and rust, ideal for removing scale from dishwashers, washing machines, laundry sinks, bathtubs, toilet bowls, drains, showerheads and tapware
https://www.bunnings.com.au/hillmark-375g-scalex-appliance-descaler_p4469185
Scalex is the Bunnings ‘miracle’ cleaner you need to try in your toilet
Cited text: Scalex is a heavy-duty home descaler by Hillmark that removes calcium, lime and rust. It can also be used to descale home appliances, clean white or p...
Excerpt: Scalex is a heavy-duty home descaler by Hillmark that removes calcium, lime and rust.
https://www.bhg.com.au/lifestyle/cleaning/scalex-for-cleaning-toilets/
Hillmark Scalex Heavy Duty Home Descaler 375g reviews | ProductReview.com.au
Cited text: Scalex Heavy Duty (available at Bunnings) used overnight one night only.
Excerpt: One user left Scalex Heavy Duty overnight and within 10 minutes the next morning, 'a quick scrub and stain was gone.
https://www.productreview.com.au/listings/hillmark-scalex
Hillmark Scalex Heavy Duty Home Descaler 375g reviews | ProductReview.com.au
Cited text: Within 10 mins , a quick scrub and stain was gone. Toilet looks brilliant.
Excerpt: One user left Scalex Heavy Duty overnight and within 10 minutes the next morning, 'a quick scrub and stain was gone.
https://www.productreview.com.au/listings/hillmark-scalex
Best way to clean very dark scale in toilet bowls—Cleaning discussion
Cited text: Just poured about 1 or 2 spoonfuls into the bowl and left it overnight. Quick scrub with the dunny brush in the morning and then flushed. Scale all go...
Excerpt: Another satisfied customer simply 'poured about 1 or 2 spoonfuls into the bowl and left it overnight.
https://forums.whirlpool.net.au/archive/9wj588m3
Scalex by Hillmark from Bunnings: the best product to clean your black toilet stains | New Idea
Cited text: (Credit: Mums Who Clean/Facebook)Said member Louise: ‘SCALEX


Look at the comparison
’Before anyone judges me no i am not a filthy person.
Excerpt: 'Before anyone judges me no i am not a filthy person... I rent the property and the first pic is how the toilet was when i moved in i had tried everything'
https://www.newidea.com.au/food/bunnings-miracle-toliet-stains-hack/
Scalex by Hillmark from Bunnings: the best product to clean your black toilet stains | New Idea
Cited text: I rent the property and the first pic is how the toilet was when i moved in i had tried everything.’ · Jemima was blown away by the results she receiv...
Excerpt: 'Before anyone judges me no i am not a filthy person... I rent the property and the first pic is how the toilet was when i moved in i had tried everything'
https://www.newidea.com.au/food/bunnings-miracle-toliet-stains-hack/
'Amazing' $12 Bunnings product saves households hundreds
Cited text: One woman even replaced her toilets over the issue, and with the average loo setting you back almost $500 spent hundreds more than the budget fix this...
Excerpt: One woman even replaced her toilets over the issue, and with the average loo setting you back almost $500 spent hundreds more than the budget fix
https://au.lifestyle.yahoo.com/bunn...g-stain-remover-eleven-dollars-033010262.html
Limescale? in Toilet—How to Remove? - OzBargain Forums
Cited text: Hillmark Scalex at Bunnings etc is 100 per cent powder, and you'll find a bunch of other products there with diluted sulfamic acid as the active ingredient, l...
Excerpt: Scalex contains sulfamic acid as the active ingredient
https://www.ozbargain.com.au/node/778721
Limescale? in Toilet—How to Remove? - OzBargain Forums
Cited text: Look up “sulfamic acid” (NOT sulphuric acid) Buy some at Bunnings in powder form.
Excerpt: Scalex contains sulfamic acid as the active ingredient
https://www.ozbargain.com.au/node/778721
Hillmark 375g Scalex Appliance Descaler—Bunnings Australia
Cited text: *Avoid contact with stainless steel cutlery containing chrome as it may be permanently tarnished.
Excerpt: it may cause permanent tarnishing
https://www.bunnings.com.au/hillmark-375g-scalex-appliance-descaler_p4469185
Hillmark 375g Scalex Appliance Descaler—Bunnings Australia
Cited text: It’s ideal for removing scale from dishwashers, washing machines, laundry sinks, bathtubs, toilet bowls, drains, showerheads and tapware.
Excerpt: The versatility of Scalex extends to dishwashers, washing machines, laundry sinks, bathtubs, drains, showerheads and tapware
https://www.bunnings.com.au/hillmark-375g-scalex-appliance-descaler_p4469185
Hillmark SCALEX Removes Rust Stains, Lime And Mineral Deposits 375g Cleaner | eBay
Cited text: I originally purchased the scalex for cleaning my old toilet bowel and I worked a treat. I decided try a mixed solution on my shower screen, and it wa...
Excerpt: One user reported: 'I originally purchased the scalex for cleaning my old toilet bowel and I worked a treat.
https://www.ebay.com/itm/251884823647