Tired of Stubborn Grout Stains in Your Shower?
If you’re frustrated by those black or pink stains in your shower grout, you’re not alone. It’s one of the most common complaints we hear from our house cleaning service clients — and no matter how often you clean, the stains seem to come back.
We’ve Helped Countless Clients Solve This — and You Can Too
As a professional house and commercial cleaning service, we’ve removed mould from hundreds of bathrooms.
The good news? You don’t need expensive products or specialised tools.
In this guide, we’ll show you how to get rid of mould safely, effectively, and for as little as 10 cents — using methods we use in our professional cleaning jobs.
What You’ll Learn in This Guide
✅ What causes red and black grout stains
✅ Which cleaning products are most effective
✅ How to make your own mould remover at 1/50th the cost
✅ Step-by-step instructions using basic tools
What’s Causing the Stains in Your Grout?
Red or Pink Stains
These are caused by Rhodotorula, a red yeast or bacteria that thrives in damp environments. While harmless to most people, it gives the grout an unhygienic appearance.
Black Stains
These are caused by mould, commonly Stachybotrys chartarum or Aspergillus species.
Besides looking unpleasant, mould can pose health risks — especially for people with allergies or asthma. Symptoms may include coughing, sneezing, and fatigue.
The Best Way to Clean Mould from Shower Grout
Fortunately, the process is straightforward — and you don’t need to hire a house cleaning service just to remove shower mould. With the right cleaner and brush, you can get it done yourself.
Option 1: Store-Bought Mould Removers
Brands like Mould Away, Mould Killer, and Mould Off are widely available at supermarkets and hardware stores. They usually cost $5–$7.50 for 500ml.
Most contain nearly identical ingredients — so feel free to choose the most affordable one.
Option 2: DIY Mould Remover for Just 10 Cents
Most commercial products are bleach-based. The main active ingredient is sodium hypochlorite (aka bleach). That strong smell? That’s bleach doing its job.
Here’s the trick: by mixing bleach with cold water at a 10% concentration, you can make an equally effective mould remover at home for just 10 cents per bottle.
Cost Breakdown
- Store-bought remover: $5–$7.50 per 500ml
- DIY version: 50ml bleach + 450ml water = $0.10 per 500ml
That’s up to 75x cheaper, with no loss in effectiveness.
How to Make Your Own Mould Remover
⚠️ Always wear gloves and safety goggles when handling bleach. Never use hot water or mix bleach with other cleaners.
- Use a clean spray bottle.
- Add 10% bleach. (use a funnel if needed)
- Fill the rest with cold water.
- Seal and label the bottle.
Tools You’ll Need
You don’t need professional-grade tools. A simple toilet or tile brush from the supermarket or Bunnings will do.
Here’s what we use in our commercial cleaning services:
- A wide-head brush for mosaic tiles
- A narrow brush for tight corners
- A general-purpose scrub brush for larger grout lines
How to Clean Grout Mould – Step by Step
- Ventilate the bathroom by opening windows or turning on the fan.
- Spray the cleaner onto the affected grout lines.
- Let it sit briefly, then scrub with a brush.
- Rinse thoroughly with clean water.
⚠️ Never mix bleach with acidic cleaners (like vinegar or toilet cleaner) — it can release toxic chlorine gas.
⚠️ If mould has been there for too long, black stains may become permanent. Clean it as soon as you notice any mould to prevent lasting discolouration.
What If the Mould Stains Won’t Come Out?
If mould has been left for too long, it can leave deep black stains in the grout that even bleach can’t remove.
In these cases, you have two main options:
- Cover it up: Use a grout pen to paint over the discoloured lines. This instantly improves the appearance without replacing the grout.
- Replace it: For the best long-term result, consider re-grouting — removing the old grout and applying fresh grout. This restores the original look and helps prevent future mould growth.
What About the “Spray and Leave” Method?
Some people spray mould remover and walk away. It can work, but it may leave unsightly drip marks on tiles or grout if not rinsed. That’s why we recommend brushing and rinsing thoroughly — a method we always use in our house and commercial cleaning services.
How to Prevent Mould from Coming Back
- Dry the area with a squeegee or cloth after each shower.
- Ventilate well — leave the window open or fan on for 10–15 minutes after use.
- Clean regularly at the first sign of stains. The sooner you act, the easier the removal.
But let’s be honest — all of this sounds simple in theory, but in reality, it’s easy to fall behind.
And grout mould isn’t the only issue in the shower. Over time, soap scum can also build up on tiles and glass screens, leaving behind cloudy stains and stubborn residue.
If you’re also dealing with soap scum, check out our guide:
👉 How to Remove Soap Scum from Shower Screens – Fast and Easy
Don’t Have Time? Leave It to the Pros.
We understand — bathroom maintenance is time-consuming and easy to put off.
If you’re short on time or just want spotless results, our house cleaning service is ready to help.
For business owners, our trusted commercial cleaning service keeps facilities fresh, hygienic, and guest-ready — without relying on your staff.
📞 Contact us today for a personalised quote and enjoy a bathroom that looks as clean as it feels.
