This is a bit sad I know...
but when me and my brother were kids we used to buy chewing gum that came in the form of small tablets and pretend that it was 'oxygum'. Many an hour was whiled away pretending that we were 'Marine Boy' !!
I watched it somewhere between February 1971 and August 1972. I'm specific about the dates because I know which house I was living in. That's all I can remember about it, though. Of course, I was practically a babe in arms at the time....