Remove mushrooms and lichens from the terrace

My terrace stones (red clinker) are now almost 20 years old and have gotten numerous stains from fungi and lichens. I went over them with the Kärcher, but that hardly helped. How do I get this ugly "patina" off?

There are so-called Grünbelagentferner, with which you can remove organic deposits/contaminations, give it a try.

Hi,

I have already tried quite a few things. Baking powder, vinegar solution, etc. The success was moderate. Now I also got a tip with such a [Grünbelagentferner]. I then bought a 5-liter canister at Hornbach. It cost 11.50 CHF back then. I applied it with a brush and let it sit for 2 days. Wonderful, everything is gone.

Hello Marcel,

Thank you for your note and I also have the problem. I will go to Hornbach next week and I hope they have this [Grünbelagentferner] on offer. The price also seems to be okay.

Yes, the price is acceptable. I also got it and applied it immediately. Wonderful result, finally those ugly stains are gone. I will now use it regularly.

Hello,

That is a good tip, because I also need to do something about these ugly stains. Now I have to see if I can find such a [Grünbelagentferner] at Hornbach. Maybe it is also available at another hardware store.

Best regards and have a nice Sunday.