Here is a question I get periodically from my customers
As in the attached sample pics, why would I get this scale buildup behind my triple filter set- 5 micron -> 1 micron -> .5 micron carbon? I maintain the filters.
B - Full time RV'er
Scaling is caused by hard water. Hard water is water with a high pH and lots of minerals, especially calcium and magnesium. In hard water, these minerals are fully dissolved in the water, so even a .2 micron ceramic filter or a 0.5 micron carbon block filter is not small enough to remove them. To get them out requires a water softener or reverse osmosis. I would recommend a Double Standard On the Go to soften the water and remove calcium and magnesium.