Chola mounts (as with most mounts) tend to dry quickly so it is pretty hard to overwater. Having said that, for me, two factors govern. Relative humidity in the location (mine tends high) and plant requirements. That barkeria and other similar types get water maybe 3x per week. If temps high I could water every day if need be.
I like to mount plants because the roots get lots of air and as we know ITS ALL ABOUT THE ROOTS.