I have a 15Watt fluorescent bulb in my tanks. I have java fern with java moss on driftwood, cryptocoryne wendii red, vallisneria, wisteria,dwarf sagittaria,and a sword plant that I have to put florish or root tabs in once in awhile. No Co2 and in pool filter sand and they are all doing good. One tank is a 30 gal. high and and the others are standard. with 1 15Watt fluorescent bulb. I have java moss, hornwort,crystal wort or Ricca floating on the surface of some of the tanks for baby fish to hide in.