I have a 20 gallon planted community tank which is my favorite tank. I actually just updated my profile with 2 pictures of it and updated the info about it.
Few things about my tank that seems to work for me:
Substrate: Sand
Co2: Nutrafin Plant System Co2 that hangs on side of tank, my plants grow much better when Co2 is present. Ive also found a constant Co2 injection over dosing with Flourish Excel is better, least in my case.
Filter: Whisper Power Filter for 20 gal
Ferts: I dose with Flourish Comprehensive Plant Sup. & Flourish Trace
Plants: Mostly fast growing plants, which I trim every week or so when i do my 20% water change. Those plants grow nicely and usually I have to trim them because they will cover the surface and then it gets dark in the tank.
Few slower growing plants, like
Java Fern. My
Java Fern leaves dont get real big, but there are lots of little leaves growing off of the mother fern that I first put in there, which I have used to decorate 2 other tanks in my house with.
Light: I tried fluorescent lighting over the tank, but didnt see great results, granted I'm a college student and dont have the money for some of the higher end stuff. I got an older incandesent top out of storage and put 2 spiral bulbs in it, in the range of 3-4 wpg. Works pretty good for me.
I see very little algae in the tank, and whatever does grow, usually happens when my co2 runs out(which is a good hint for me to start a new batch of yeast), but I have 2 oto's in the tank amongst some shrimp and they keep it pretty nice looking. I also have several Rams in the tank that find it pretty comfortable since they spawn just about every week and a half.