In article ,
says...
I have been curious how people who have heavily planted lush 'forests'
vacuum regularly. I presume they don't, but then why don't they get
anaroebic (sp?) build up in their substrate (which I do prefer to use a thin
layer of).

Seems to me I read somewhere that the plants minimize that possibility
as well. Others can comment if they know more.

And a couple of catfish keep at least the top layer stirred up pretty
well :-).

--
Homo sapiens is a goal, not a description