I think you will find that most rec.ponders will vote for no gravel.
Just makes it a whole bunch harder to clean.
It is a pond's nature to fill in. Blown in dirt, fish waste, dead plant matter.
Eventually all natural ponds will fill in unless they get dredged out by man or
mother nature (she usually does it with a raging flood).
We don't want our ponds to fill in so we take steps to keep it from happening
by skimming, trimming plants, netting leaves, adding sludge eating bacteria,
and finally cleaning them out. Gravel just gets in the way.
You can clean around large rocks, still a bit of a hassle, but if you like the
look it may be worth the trouble.

k30a
and the watergardening labradors
http://www.geocities.com/watergarden...dors/home.html