Spring Resolution: Get Serious About my Plants

Hi Guys.

I've always enjoyed aquatic plants in my aquariums but haven't really
ever taken it seriously. Aside from some crypts and java moss that have
been growing beautifully my other plants don't really do well. Even my
java ferns have browned over time.

Can you guys offer me any advice on how to be a better aqua-gardener?

Right now, all my tanks are well established and range from 5.5 gal to
30 gal. The pH is between 6.9 and 7.4 depending on the tank. GH is 10Ëš
and KH is 3Ëš.

I have Coralife fluorescent tubes for lighting, which are all well more
than a year old and need replacing and I use fertilizer pellets made by
aquariumplants.com under most of the plants. The substrate varies in
each tank and includes sand, gravel or flourite.

Do I need a CO2 system and a fancy lighting set up to get better
results? I would consider spending a little more if I thought it was
really worth it.

I appreciate your help.

-Christie