That may be true for some plants, such as hornwort or anacharis, which
seem to grow no matter what you do to them, but there are a great many
that simply won't flourish in gravel. For example, swords crave a very
rich sub, which I've found requires a denser material, like sand.



Swords is the bulk of what I grow very successfully in gravel. In fact
I have so many varieties of Echinodorus growing in gravel that I had to
post again and tell ya that that is not true.

Vicki