Texas aquatic plants/PMDD

 > I am a marine biologist with the Texas Parks and Wildlife 
 > Department.        We have five species of seagrasses in 
 > Texas--Thalassia testudinum       
I don't really dabble in the marine side, but since I do live in West Texas, I 
was wondering what FW grasses and plants that I might be able to find. Any 
help/source would be great.
A couple of weeks ago, somebody posted a bunch of info on PMDD, including a 
person that was willing to do the mixing, for a price. I thought I kept that 
info, but can't seem to find it. Could somebody please repost that, so I can 
part with some of my money?
One more question,  I have a 100 gal tank with a UGF on one side, and I'd like 
to put a richer
on the other half of the tank. Any suggestions on substrate composition, and how 
I might accomplish
this without making a complete mess (and without having to drain the tank, which 
is probably wishful