Reddit reviews TFA-Dostmann Thermometer-Hygrometer Instrument Room Control Anthrazit-White

I can't help you with your current situation, but generally once you have mould you'll always have it, as there are always mould spores floating about. They like high humidity and warmth which is abundant in Edinburgh flats. Cheap quality chests of drawers and wardrobes are usually the culprit too as they haven't been treated with anti-mould paint\spray.

If you can afford it, or any landlords are reading this you should provide the flat with a good quality dehumdifier, one that has a laundry setting. I have a nice little 10l one and I take it with me from flat to flat.

Get a good quality digital hygrometer and thermometer that has a min\max setting, like this one.

I also make a mould check part of my daily cleaning routine

Daily:

• You will exhale 2litres of water into the air during a night's sleep, and that moisture has to go somewhere, so ventilate the bedroom.
  
  
• Check behind the wardrobes for signs of mould
  
  
• Run a fan\heater so it circulates the air around the bedroom
  
  
• Leave the dehumidifier on its medium setting and go to work. If you don't have one, then at least make sure the room is well ventilated before you leave.
  
  
  Weekly:
  
  
• A better check of the usual mould hotspots
  
  
• Bleach\Water solution on the black mould if it appears (bathroom usually)
  
  
• Use a vinger\water or ethanol\water solution and rub down the back of the warddrobe. Kills white\blue mold spores hiding there.
  
  
• Close the bedroom door and run the dehumidifier on its highest setting for a few hours