Originally Posted by tophat665
Ideally, get yourself a 130 watt Compact Fluorescent strip light. ...
I am or have been in what I believe to be a situation similar to yours.
My Tenecor tank came with some "high end" lighting but the ballast generated sufficient heat such that Tenecor placed the ballast in the wet/dry sump area of the aquarium (big time "slobber up" by them as the ballast did not last two months).
When I reentered the hobby approximately 8 months ago after 35 years I had thoroughly researched the literature wrt plants and purchased many "high end" plants. Alas plant death soon followed as IMHO this "planted tank business" is "way more knowledge gained from experience than knowledge gained from the literature".
CE and others have way more experience than I do but you may be trying to accomplish "something like in the photograph of my aquarium" (please excuse the looks as it is in experimentation mode with the canopy and wet/dry access hatch off).
The "watts/gallon" rules which you are quoting are "rules of thumb".
My tank is 20" wide and 36" long.
It is also 30" deep.
When the "old ballast" went out I purchased a 24"
with one blue actnic bulb. (the lunar light on these does not function).
The plants in the upper portion of the tank "did good" (Reason I was asking you about the depth of your tank) but the "planted" plants started dying.
I purchased a 2nd one and as you can tell from the photograph all the plants are doing good (I am currently experimenting with 3 white bulbs and 1 blue bulb as well as lighting periods.)
The goal of the experimentation is "the nicest looking plants possible" with minimal or no algae.
While Ce and others have more experience than I do I have never used CO2 but have used "Flourish" (The correct dosage of Flourish will actually decrease the quantity of algae in the tank!)
I am trying to gain experience in order to grow more exotic (and nicer looking) plants.
If you have any questions please post.