I live in a cool, damp climate with extremely hard water. Both spots in question are located in a poorly ventilated bathroom. The first spot (first photo) won’t respond to vinegar (8%) or a store-bought mildew/mold cleaner. After scrubbing the second spot (admittedly too hard; second photo), it stripped the paint, but left behind a rust-colored stain with a black hole in the center.
For additional context, I recently discovered black mold in the bedroom, next to the door to a terrace, but it responded to vinegar treatment.
Importantly, my wife and baby are both immunocompromised. My wife is recovering from pneumonia and was recently diagnosed with a severe allergy to Alternaria. After being away for several days, she immediately started sneezing upon entering the bathroom.
We live in a rented apartment. We’re considering calling a third party to diagnose, and in the worst case, potentially moving, but don’t want to make any rash decisions.
Happy to provide any additional information. Thanks for any advice.