This is what we need to know to give meaningful advice. By lighting, we mean what kind of light, T8, CFL, T5HO, T5NO, etc. and hopefully who made the light fixture.
Should have mentioned:
The lighting is from Coralife, the one that fits with the 20 gallon tank, with "high output" (according to the box) T5 lights offering 10,000K and 24 watts.
[looks like this: http://www.shopping.com/Coralife-Cor...-Coralife/info
The substrate is a dark rock mixture (I forget the brand) that is specifically meant for growing live plants.
I believe the soil and lights are appropriate, but still no flourishing.
Perhaps, I should just do more frequent water changes? Would they really react that much to this? Are they highly sensitive to nitrates (I change when I go from yellow to orange (12.5 mg/l)?
I think there's something I'm missing (or have too much of) in the water.