Koh Universal Surface cleaner does an adequate job for light to medium cleans, but don’t expect it to be a miracle solution for heavier cleans on older stains and surfaces. We also found Koh failed to outperform water and a microfibre cloth for cleaning a stove top and shower screen.
Aussie eco-cleaning company Koh (formerly EcoWorx) says its mission is to eliminate toxic chemicals and simplify the process of cleaning your home by using just one product: Koh's Universal Surface Cleaner.
Koh's social media is flooded with images of its mystical and magical cleaning powers, including layers of oven grease disappearing with just the spray of their universal cleaner.
Ready to be converted by this cult cleaner, I spent a week with Koh's Home Starter Bundle.
Although it did an OK job, it definitely didn't live up to the hype.
Amira with her Koh home starter bundle.
What is Koh cleaner?
Koh was created by two dads with the aim of eliminating the use of toxic chemicals in home cleaning products.
Their Home Starter Bundle arrived at my door in a compact box containing what I needed to begin my toxic-chemical free cleaning journey: the Universal Surface Cleaner, a spray bottle, four microfibre cloths and four diamond sponges.
The universal cleaning solution, as its name would suggest, claims to clean just about anything from glass to fabric. It comes in a container resembling a wine cask, with a nozzle to pour the solution into your reusable spray bottle.
Koh's colour coding
A distinctive feature of Koh is that it comes with colour-coded microfibre cloths and sponges for general cleans, bathroom cleans, and window/glass cleans. The black diamond sponge is essentially an abrasive sponge with a sandpaper-like texture that targets tough stains and marks.
If you own a spray mop you can also use Koh as a floor cleaner. Or you can buy Koh's Spray Mop Bundle ($98.80), which includes a mop and five reusable pads.
What's in Koh?
Koh Universal Surface Cleaner is made up of a mix of pure water and potassium mineral salts.
Is it antibacterial?
No. Koh Universal Cleaner doesn't work as a disinfectant or sanitiser. But in late 2020, Koh launched a new spray product – Protect Surface sanitiser – which they claim is "clinically proven to kill 99.9% of bacteria and keep household surfaces bacteria free for 7 days, even with regular cleaning".
However, neither product has been proven to kill viruses such as COVID-19.
How easy is Koh to use?
Overall, it's easy to use. The combination of the colour-coded wipes, easy-to-follow instruction booklet and the universal cleaner made for a simple cleaning process.
The reusable spray bottle turns the universal cleaner solution into a fine mist, which made it easy to get an even spread of solution on dirty surfaces. For tougher stains, Koh suggests leaving the solution on for two to three minutes before wiping.
Cleaning the cleaners
I love anything I can just throw into the wash and not worry about, and luckily you can do just that with Koh's microfibre cloths.
Their website says you can wash the cloths on a 60–80°C cycle with normal detergent. I accidentally washed the cloths on a cold cycle and they still came out nice and clean.
Does Koh work?
For 'light' cleans…
The combination of the universal cleaner and blue bathroom microfibre cloth did an excellent job of cleaning my bathroom sink and cabinet.
The white window and glass microfibre cloth did an OK job at cleaning my bathroom mirror. But the solution left streaks on my mirror, which I could only remove after some vigorous wiping.
Bathroom sink before and after use of Koh.
For 'heavy' cleans
For heavy cleans such as ovens, cookers and shower screens, Koh suggests applying a "full spray" on dry surfaces, leaving it for two to three minutes – before wiping with a dry cloth or using a dampened diamond sponge for tougher jobs.
I tried three heavy cleans with Koh's universal cleaner, green microfibre cloth and diamond sponge.
I started with my least favourite cleaning job… the grotty rim of my shower screen door.
After five minutes of scrubbing I gave in to the grot and put away the diamond sponge
Although there's a certain amount of elbow grease expected when it comes to heavier cleans, after five minutes of scrubbing with the diamond sponge I gave in to the grot and put away the sponge.
It certainly wasn't the satisfying cleaning experience I'd expected from watching Koh's videos.
Shower screen door before and after use of Koh.
Next I ventured to the greasy inside of the oven door.
I let the solution sit for three minutes then again got to work with the diamond sponge. Although it did get rid of the top layer of grease, the door still didn't look or feel completely clean – and the grease certainly didn't melt away with just a spray as it does in this video on Koh's Facebook page.
Oven door before and after use of Koh.
My final heavy clean with Koh was my balcony doors.
Having not been cleaned for several months, they were in bad shape. I cleaned one side of the doors with the universal cleaning solution and a green microfibre cloth. Koh lifted the layer of dirt from the door, but didn't lift any of the stains.
Can you use Koh on fabric?
I was skeptical about using Koh on fabric, and so I should have been.
I used a single spray of the Universal Surface Cleaner on a small stain on my sofa. A week later the stain was still there – along with a new stain where I sprayed the solution!
Koh warns that you should always test the solution on an inconspicuous place first. So if you're experimenting with Koh on fabrics, don't do what I did – instead, follow the directions and proceed with caution!
What about leather?
Yes, you can use Koh on leather, although you should spot test first. If there's no reaction, go ahead with your clean. Give it a light spray, leave for a few seconds, then wipe it off with your microfibre cloth.
Couch stain before and after use of Koh.
Koh Universal Surface Cleaner vs water
Koh's Universal Surface Cleaner is made up of pure water and potassium hydroxide – an inorganic compound used to make soap and cleaning solutions (you may have heard it called caustic potash or lye).
Potassium hydroxide is also used as an electrolyte in alkaline batteries, as a food stabiliser, and can be found in some liquid drain cleaners at levels up to 36%. (Fun fact: KOH is the chemical formula for potassium hydroxide.)
But with potassium hydroxide making up less than 0.5% of the cleaner's active ingredients, I wondered if the microfibre cloths were actually doing most of the work.
Again, Koh failed to outperform water
I put this to the test by spraying one half of my cruddy stove top with Koh and the other half with water, then cleaning each side with the microfibre cloths.
The results were almost identical.
Earning a crust?
Although neither Koh nor water could fully remove the crust around my stove lights (gross!), they both partly removed the crust, and fully removed any other spills or grease stains on the metal stove top.
Next, Koh's universal cleaning solution battled it out against water on my shower screen.
Again, Koh failed to outperform water.
Although both halves of my shower screen were left free of shampoo and soap marks, there were still some light streaks on the glass, even after vigorous wiping with Koh's white window/glass microfibre cloth.
It looks as if I'll be going back to my trusty ball of newspaper to get rid of streaks on glass.
With Koh (left), with water (right).
One of Koh's biggest selling points is that it's an eco-friendly cleaning system, with its reusable spray bottle and cloths.
The other big plus is that it's free from toxic-chemicals, which makes it a good option for people with asthma and allergies. It's even been approved by the National Asthma Council of Australia's Sensitive Choice Program.
Koh is also certified by the Good Environmental Choice Australia (GECA). GECA-certified products can have a lower impact on the environment and be safer to use than harsher cleaning products.
Stock images: Getty, unless otherwise stated.