Advice on Substrate

Hello All,

I've been browsing for a month now, trying to learn as much as I can
before I set up my 140 gallon tank. 50"x27"x24" planted aquarium.
I would like to use regular aquarium gravel, I've read where some folks
do this, and wonder if adding anything to the gravel would improve changes
for success?  Also, my tank will be coming with a drilled overflow chamber,
this will provide surface skimming. Would this be a problem?  I also
plan to use a fluidized bed filter in the sump.  I'd like to hear your
comments on my plan. Thanks!  Todd