Don't go overboard ording equipment such as CO2 until you have your
lights in order. Although not a great rule, I would suggest you aim
for 2-3 watts per gallon to start. Plants need enough light to
photosynthesize. Each plant has a minimum amount of light they need
in order to photosynthesize enough to provide it with its minimum
requirements. As you have many different species in your aquarium,
you must focus on satisfying your most demanding plant as the others
will, by default, receive enough light.

Regards,

Art Giacosa
http://www.aquaticplantcentral.com