I Meant what i said in a practical way. Technically what I meant was if
a human lived in a glass room totally sealed off from the environment,
the size of a bedroom and never got new air for over a month at a time
that air would be horrible if not deadly by the time that over a month
new supply of air arrived. That's basically what I meant and it is
practically comparable to keeping fish in a glass tank, those fish and
other organisms (invertebrates, plants) don't have acres of land or
water enough for natural processes to renew their breathing water. You
are right by what you say but I think you misunderstood what I meant.
I'm glad you agree that a change of some water regularly is better than
not though. Later!