Mould in tile grout is a common issue due to its porous nature, excess moisture, and inadequate ventilation. Black, brown, and yellow stains recently appeared on my bathroom grout, making the space look unclean despite deep cleaning. Natural remedies like white vinegar and bicarbonate of soda failed to remove the stains effectively.
Products Tested
To find the best solution, I compared three popular mould removers on affected grout areas:
- Mould Magic: A thick gel costing £12.99 for two tubes, available from Must Have Ideas. It promises to eliminate 100% of mould in one application.
- Astonish Mould & Mildew Blaster: Spray priced at £1.99 from Wilko and The Range, or £2.99 from Lakeland.
- HG Mould Spray: Foamy spray available for £4.29 at Savers or £6 at B&Q.
Testing Method
I wore gloves and dried the grout before applying each product to separate spots, preventing dilution or mixing. The stains were darkest near the shower.
First, Mould Magic gel applied easily without dripping or strong odour. Instructions require 2-3 hours dwell time.
Next, HG spray foamed and clung well, though some ran down tiles. It needs 30 minutes, but its bleach-like smell requires good ventilation.
Astonish spray, the most liquid, was left on for 10 minutes per instructions for stubborn stains. It has a noticeable but milder scent.
Results
Astonish Mould & Mildew Blaster
Expectations were low due to its watery consistency, but wiping after 10 minutes revealed clean, stain-free grout in one pass. It restored brightness quickly for a budget option.
HG Mould Spray
After 30 minutes, the mould had visibly dissolved. A quick rinse and wipe left the grout exceptionally white and renewed.
Mould Magic
The gel removed all mould effectively after 2-3 hours, with no lingering odour. However, residue was harder to rinse off completely.
Final Verdict
All three products successfully tackled grout mould. HG Mould Spray stands out for its 30-minute action, superior clean, and white finish, despite the higher price and smell. Astonish offers great value for fast results, while Mould Magic excels on sealant but takes longer and is trickier to source and remove. Prices accurate at time of testing.

