This is the main setting panel, notice that the two tanks named with "Lush Plants" and "Zen Garden", so the square stone is meant to be Zen related...but I don't see any point.
And then there's change tank slider bar, with Less often and More often tendency in two sides, the rest is self-explanatory
James C Chen
Principal Engineer as SDET, Connected Services
HTC Corporation
88 Section 3. Zhongxing Road
Xindian District, New Taipei City 231, Taiwan
www.htc.com