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 with an approach suited to your surfaces — 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 follow product dilution and surface-care instructions
✅ Step-by-step instructions using basic tools
What’s Causing the Stains in Your Grout?
Red or Pink Stains
Pink or reddish deposits can have different causes. Their colour alone does not identify an organism.
Black Stains
Black patches may be mould or discolouration. Appearance alone cannot identify a mould 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.
Formulations and suitable surfaces differ. Compare the label instructions, active ingredients and safety precautions before choosing a product.
Option 2: Follow the Product’s Dilution Instructions
Some mould removers contain sodium hypochlorite (bleach). A strong smell is not a measure of cleaning effectiveness.
Bleach strengths vary. Follow the specific product label for dilution, application and contact time; do not use a universal homemade recipe.
Choosing and Using a Cleaner
- Check that the cleaner is suitable for the grout, tiles and adjacent sealants.
- Use the dilution and application method stated on that product’s label.
Compare suitable products by their labelled use and coverage, rather than assuming a cheaper mixture gives the same result.
How to Prepare for Mould Cleaning
⚠️ Always wear gloves and safety goggles when handling bleach. Never use hot water or mix bleach with other cleaners.
- Read the product instructions before opening or preparing the cleaner.
- Follow the label’s dilution instructions, if dilution is required.
- Ventilate the room and wear the protective equipment specified on the label.
- Store the product safely in its original labelled container, away from children.
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.
For extensive or recurring mould, seek professional assessment and address the moisture source. Read the Victorian health guidance on mould removal at home before starting.