bacteria

This is a bit of a long shot but hopefully worth a try..... I've painted the walls of a bedroom with a bad batch or Dulux Emulsion which caused a sour odour once fully dried (walls had been freshly skimmed and paint didn't smell in the tin). I was advised to wash down the walls with bleach and...

Last autumn, I cleaned out the central heating system (old back boiler with F&E) with X400, and dosed with X100. It hadn't been touched for a good few years prior to that. A few months later, I find this gunge in the tank (stringy/white stuff) which Google tells me is probably bacterial and...