I was finally able to take some pictures this morning and have been wondering what this stuff is that is building up on the tile behind my waterfall. Also, how do I get rid of it?
Here are a couple of pictures. Notice in the last one that a little nipple of this stuff has formed as well.
Waterfall shut off so you can see the buildup
Here you can see the buildup as well as a little nipple that has formed as well
Thanks for the help on this one!!!