Stains are often pink or black, and stick to fittings and tiles. Sometimes, a black jelly can build up inside taps, and wash out into the sink.
This is caused by airborne spores that like to grow in warm, damp places. Bathrooms and kitchens are usually the perfect place for this to happen.
Mould, also known as biofilm, does not come from your water supply.
Fair question! There are lots of simple things we can all do to keep our kitchens and bathrooms mould-free.
Our top tips include:
Oh, and you don't need to spend a pretty penny on posh bleach products either. In fact, more expensive bleaches often contain phosphates, which help mould grow.
Get your budget-friendly bleach from any supermarket, to help keep mould at bay.