Small gravel?

[TKOS]

I thought I would post this here as I have sort of wondered about this since I started keeping fish. Often it is stated for fish like cories that small gravel is preferred. But how small is small gravel? For ease of mind sake, how small compared to the standard epoxy coated aquarium gravel that you can get anywhere? Is the standard epoxy stuff considered medium or large?

[OrionGirl]

Coming from a habitat viewpoint, you can't really compare gravel to sand. Gravel is anything < 3 inches, a handful of sand has a gritty feel. Silt is then smooth feeling.Above gravel, you have cobble (3-6), than rubble (6-12), and boulder (>12).

Of course-this is based on coldwater stream evaluations. ;) Still, I would say that gravel bigger than 2 mm.