i recently just downgraded to a 20 gal long and im sooooo very interested in a planted tank with out all the high tech maintenance. heres what i have and what im going to get... any advice on how to setup and maintain my tank?

have:
20 gal long
standard florescent lighting 20w
aquaclear filter for 50 gal
natural colored gravel (may not use this)
powerhead
heater

get:
eco complete
llots of ow to mid light plants; mosses, grasses, anubias, etc...
6-12 schooling fish

do i need to upgrade my light or can i just stick a different watt bulb in the fixture?
can i layer gravel on the bottom and the nutrient rich substrate on top?
what types of ferts do i need and how much per week?
water changes?
$40 co2 injection system?
what the hell do i do for my specific set up?!

help!
tasha

Please see Non CO2 methods

You'll need a new fixture with two bulbs, most likely. Or you can overdrive the light you have with a ballast meant for four of the same length light. Wattage has to do with length of the bulb so I don't think you'll just be able to get a brighter bulb for the same sized fixture without doing modifications in some way. DIY co2 is the cheapest option, if you want to do co2. Other options are Excel or non-co2. Fertilizers are cheap. You need KNO3, KH2PO4, K2SO4 and a trace mix. Also GH booster if your GH is below 3.