Theres actually two basic metheds of growing plants in an aquarium. One has been around for a hundred years or more. Originally known as the balanced aquarium, it was made popular by William Innes and more recently Diana Walstead. We'll call it the Soil Method. It says that plants gather most of their food by hunting it with their roots (picture VERY slow animals).
The other has been around for about 20-30 years in one form or another we'll call the Water Column Method. This proposes that aquatic plants get most of their needs thru their leaves. This style is proposed by Dr. Tom Barr and Japanese star Tadashi Amano.
As an aside the Water Column makes more sense to me because most aquarists have cheap water testers not soil testers.
If you're interested I'll start a few how tos for Dummies (like me) on the subject. I don't have a Dr. in my name just 50 years experiance. A lot of it growing and selling hard to get plants (read PITA to grow.)
EITHER of the fertilizing methods work. Some plants just respond better to one type than the other and the water column type is just easier to control but all plants will grow just fine with either one. All plant use oxygen and food to survive, they just use carbon from the air intead of eating it. It just depends on which one you like.
Light? as long as its intense enough (the watts per gal rule is close enough unless you're doing a scientific study) most plants will grow just fine. Plants can and do learn to use the range of spectrum you give them and the best growth I ever got was with cheap flouresent GE daylite bulbs at 2 watts per gal....Thanks, Jim
Edited by jimjim, 20 April 2008 - 07:07 PM.