It would be nice if they said what kind of filter to use. Would a paper filter from a coffee brewer do the job? Or do you need a fancier filter like campers u

It would be nice if they said what kind of filter to use. Would a paper filter from a coffee brewer do the job? Or do you need a fancier filter like campers use, to remove bacteria from pond water? Does the water still have to be boiling hot when you filter it? That's fine for coffee filters, not great for the other kind. I saw a mention of metal strainers but it wasn't clear whether that was only for larger chunks of scale.