RE: Newbie Design

["Eric Wahlig" <ewahlig at earthlink_net>]

Warhau,

"Spend that money on fish, better lighting, and a
good C02 system that you can trust." [quoting someone; I forgot who]
  
"Better lighting than 392W of power compact? I was under the impression
that,
formulaically, 3.26W/g would be sufficient to grow just about anything."
[warhau]

Your lighting is fine. The "watts / gallon" rule is based on standard
shaped tanks of a "medium" size range. The rule deviates substantially when
applied to small or large tanks or odd shaped tanks or tall or short tanks.
Its been accepted and used because, historically, aquariums were
commercially available only in the medium sized standard rectangular shapes
and this value is what got published.
If I recall correctly, you have a six foot long 120 gallon tank? The rule
works well for this tank as it is a standard shape and size. If you had a
tall tank of the same base area, like a 180 gallon, you might want a little
more light (depending, of course, on what you wanted to grow). Conversely,
if you had a short tank with the same base area you could use less light.
I invested in a cheap Sub-Lux meter when they first came out and it has
really helped me understand what light levels are present at different
depths of a tank and the affects of dense overgrowth etc. It is amazing to
see that some supposedly high light plants can grow on very little light if
the conditions are correct. 

 --- Eric