The plant looks like it's either Hornwort or Cabomba which I'm more inclined to think since Petco is where I got some Cabomba I used to have. The Petco guy threw it in with a Bamboo Shrimp so I really wasn't trying to maintain it. Assuming it's Cabomba, I kept mine in a 10gal with an incandescent bulb and it did ok. It lost a bunch of needles at first, but it did grow a bit later.
Hornwort's an OK low light plant, Cabomba is more of a moderate light plant. I know you want it to do well, but I'd say leave it for now and see how it does. Liquid ferts like seachem comprehensive should help it. Hopefully someone who's kept them can give you better advise.
75g Planted Barbs Denison, BlackRuby, Tiger, Albino Tiger, Green Tiger, Cherry, Gold, Checkered, Odessa.
NonBarbs Cardinal, Neon, RummyNose, Bloodfin Tetras, Z. Danios. 1RTS. Amano, Bamboo, Ghost & RCS. 20g Long Shrimp Tank RCS, Tiger, Amano.