Terrace slabs are spotted

Hello everyone,

we had terrace slabs from the company Kann "Madison" installed on the covered balcony of our new condominium.
These have a "CleanKeeper plus" sealant. I noticed that they scratch very quickly, I had attributed that to the grit. I scrubbed the slabs individually with water and dish soap and now there are brownish stains visible. What am I doing wrong? The slabs look so dull. I can't get rid of the stains.
Does anyone have any advice?

Do you have oiled wooden furniture on the terrace? That also causes such brownish stains because the oil seeps out a bit. We use this outdoor cleaner from Lithofin for dirty concrete stones, it always works for us.

Best regards
Sabine

Thank you Curly for your prompt response. May I also use this "Lithofin" on these tiles with "CleanKeeper plus" sealing? Meanwhile, I am afraid of what I can do.

Thank you Curly for your quick response. May I also use this "Lithofin" on these slabs with "CleanKeeper plus" sealing? By now, I am afraid of what I can do.

Ask the manufacturer

I use soft soap, a scrub brush, and patience. Once a year and everything has come off so far. Grease stains, algae growth, etc. However, they are not particularly sealed.

Email the manufacturer with the photos and ask...