Thanks for all the advice here.
Since it rained after laying the concrete, there have been patches on the concrete. Concreter is suggesting painting over it. Will that suffice? Or does it need grinding? Photo attached.
Thanks
Thankyou for your advice. We do have Caesar coming out and hopefully resolve the issue for us.
Probably efflorescence Salts coming out of sand, cement products and mortar Water brings them to surface and when evaporates it stays Extremely difficult to get rid of