I found a great source for Manzanita... Blooms and Branches. (Google it... I'm at the airport right now). I bought a large, nice selection for $50. I have tons left after scaping my new 75g. I'm sure it's cheaper to buy larger quantities (because of the shipping) but they sell by the piece, or maybe you could order some with a group of people.
I think the ludwiga and vals would fare better dosing with Brightwell aquatics FlorinFE and FlorinAxis. Cheapest at LNT.com, which has no shipping charges.
The FlorinAxis may help with the algae. For it is a Co2 replacement. It is not as good as Seachem Excel but will not affect the Vals, which are sensitive to Excel.
What color is the algae? Brown algae is normal for the beginning of a tank.
Algae is brown. I am dosing with Flourish Comprehensive, not Excel.
I will check out the chems you recommended. I'm totally in the dark when it comes to nutrients. It was suggested to me by someone here that I might have a macro deficiency, so that's why I bought the Flourish Comprehensive.