What can I expect from this lighting system?
 

I am setting up my first legitimate planted tank and would like to know what I can expect from the lighting system I’m planning. My goal is to support a 36” x 18” x 20” (aprox 55 gallons) moderately planted tank without CO2 additions. I don’t have any particular plants in mind or lighting goals beyond supporting a fair variety of plants without specialty equipment.

The plan is to use 4 spiral CFLs (23w, 6500K) in parabolic reflectors. The bulbs will be vertically oriented and suspended about 2 inches above the water level and a total of about 20 inches above the furthest planted portion of the substrate.

I know there are several other variables in play but, assuming lighting is the limiting factor, what can I expect from such a set-up as far as plant choices are concerned? What can I grow and what should I avoid? I’m hoping to avoid buying plants that require more light than I can provide. Any insight would be greatly appreciated! :icon_bigg

And to tack on a couple more questions:

How much of a difference is there in parabolic and box style reflectors?

Would I use a different orientation (horizontal) for a box style reflector?