I'm considering planting some aquatic plants in pots or in "planting
rocks"
(from the Foster & Smith catalog).

I wish I had responded with this question last week when someone wrote
that
plants get most of their nutrients from the water.

Can I put just plain aquarium gravel in these pots, or should I use
SeaChem's Flourite or ...what?

Thanks in advance for your recommendations.

Most of my stuff is in pots. I've used flourite, beach sand over
a mix of Farfards aquatic soil mixed with profile (ran out of flourite)
and plan beach sand (ran out of...).

I can't say I notice much of a difference.

Do you leave the hole at the bottom of the pot open? It seems that flourite
or soil would fall out, or that the iron, nitrogen, etc would get into the
water.