The combination of humidity and high temperatures are a recipe for mould. It gets everywhere. Anything that catches dust is prone to attract mould. Add a dark environment without draft and you have the perfect mould storm. During the relative dry season (from December to February) mould is less of a problem, but in the rainy season it is a constant fight against the mould.
iPad cover with mould 
Shaving belt with mould
Almost everything that we brought to Costa Rica ended up with mould: clothes, shoes, hats, anything textile. Even electronics. We eventually found mould inside Cristina’s camera and the ocular of the telescope. We also found it in any food that we would leave outside the fridge, like paprika powder or oregano.
Remedies :
1) Hang all clothes and stuff that might attract mould in a place with draft and light – preferably direct sunlight. UV light kills the mould, and the draft keeps it on the move so it is less likely to attach.
2) Wash all clothes regularly, whether you have used them or not. How regular depends on the circumstances.
3) Camera’s and optics : buy the expensive ‘weather proof’ ones. Frank’s binoculars are water and air tight and have no mould inside.
4) Choose your apartment : if you can choose, you could pay attention to how light and airy a house or apartment looks.
5) Store food in air-tight plastic containers. They may not be easy to find, but the quality of certain plastic containers that you get when you buy food may get you very far. We are very fond of the big peanut butter ‘cans’ and the containers for nuts.
6) If you have no containers, put all open food in the fridge, including the things that you usually store outside (spices, flour)
THE FLIP FLOP LIFE 