The 'visibility' of something you post to another person's page is controlled by the privacy settings of that other person's page. I believe the 'Default' is that everything you post is visible to all Zoomer Members.
As a matter of personal policy, you should assume that everything you post on the Internet will last forever and can be seen by anyone and everyone. This is particularly true of postings to a public site like Zoomers. If you need to discuss private matters between yourself and another individual, you should, at a minimum, use email or a PM (Private Messaging) system. But, even with these forms of communication, you are entirely dependant on the other person to keep the communication private and entirely dependant on the security and privacy of the computer systems at each end as well as those in between.
That you for the answer to my question and duly noted!!
It amazes me how comments under One's page name are on Google before you can press send.