I have a strange build up the bottom of my pool and can't find a topic that exactly matches. It is not really white except for a few small spots that look like a clump of baking soda has settled, but will not brush away. Wherever there is build up, you can't see the pattern on the liner (about 1/4 of bottom of pool). I tried to attach a pic but it said the file was invalid. (I am on an imac if anyone can help with that). It is a pretty clear pic so it would probably be helpful!
The build up is smooth, not rough like others have described calcium.
I have a vinyl liner, 26,000 gallons.Here are my numbers (using Taylor K-2006 kit)
CYA-30-40 (don't have R-0013 so used strip for this)
Heading to bed...took too much time trying to attach pic! will check for responses early in am.
thanks in advance for any advice!