I've bought a small box of Himi metallic gouache paints; as this is the first time trying out this medium I went for an inexpensive (relatively) brand. They're jelly gouache in individual pans.

Having seen some videos on YouTube I've realized there's a bit of to do caring for these paints, and I have questions.

1. Can I use boiled water to activate them rather than distilled?

2. Before covering them with the silicon pad and putting them away, are they supposed to be moistened?

I understand these paints can develop mould and it would be preferable to avoid this.