Clay Pots

I am wondering if you can help me with a ?  

I was wondering if a plant could be put in a tank planted in one of those
little rust colored clay pots?  I use a Bio-wheel filter with only an inch of
so of rocks. Not enough to secure a plant very well.  Although mine appear to
be doing ok, I worry about disturbing them when I am cleaning the gravel.  

One reason I was wondering about this is that I have a Amazon Sword Plant
that came in a little black pot.  I  took it out of the pot and planted it in
the rocks.  It seemed to be doing ok for awhile but now the larger leaves are
getting brownish rusty colored in spots and along the edges.  It looks like
it is sending new roots down into the rocks which is another reason I worry
about disturbing it when I vaccum the gravel.

I think also the little pots would look rather nice setting about the tank
and I have seen them in craft stores as small as 1 & 1/2 inches tall.

I would sincerely appreciate any help/advise you can offer.

Cheralyn Maturi