Okay, so in general I have come across some interesting info, but I would like to confirm and gather advice from the "experts' please 
Esentially, I have found that my 48" dual-40W flourescent fixture from the local hardware store w/ aqua-plant T8 bulbs works pretty darn well...especially for under $40 total (I just spray painted the top black and the inside silver).
Anyways, I understand the concept behind Lumens and Lumens per Watt, however, my main question is why is a 54W 4' fixture cost $90 from one location and seemingly an "Aquarium-Grade" fixture with similar specs run easily into the $300+ range!?!
The bulbs are all T5 or T8s...
Obviously I'm missing something... What is preventing me from buying an off-the-shelf garage fixture for around $80 and just paying for the $18 bulbs sperately for plant growing? Are not all T5/T8s rated for 40 or 54W not universal?
Please, if someone can point out the obvious why a DIY fixture would seemingly do the same job as an 'Aquarium" fixture for 1/4 the price? (besides the fancy cover and design)
I feel like an idiot for not being able to pick up on the obvious disconnect that I am having...
My last question is; what is really more important? Watts per Gallon or Lumens per Gallon? Intuitively, I would say Lumens are. However, with a fixture directly over a tank (practically an 1" or less from the aquarium top) are Lumens particularily important as all of the effective light is being focused anyways, or is the W/G rule just another rule-of-thumb that gets us in the ball-park? <-Understanding that Lumens and focus are critical for fixtures elivated above the tank as radiant (or lost light), as well as distance, are big factors in these styles.
This last point may be the missing 'link' as to why seemingly identical outputs vary so greatly in price as I recall most (if not all) were pictured elivated...hmm.
Thanks in advance!
CT-Death
EDIT:
90G Tank lightly planted with -- Java Fern, Moss & Lace, and Vals and Swords (wishing for a medium planted tank not requiring too much in regards to ferts/CO2, but not afraid to either).
Esentially, I have found that my 48" dual-40W flourescent fixture from the local hardware store w/ aqua-plant T8 bulbs works pretty darn well...especially for under $40 total (I just spray painted the top black and the inside silver).
Anyways, I understand the concept behind Lumens and Lumens per Watt, however, my main question is why is a 54W 4' fixture cost $90 from one location and seemingly an "Aquarium-Grade" fixture with similar specs run easily into the $300+ range!?!
The bulbs are all T5 or T8s...
Obviously I'm missing something... What is preventing me from buying an off-the-shelf garage fixture for around $80 and just paying for the $18 bulbs sperately for plant growing? Are not all T5/T8s rated for 40 or 54W not universal?
Please, if someone can point out the obvious why a DIY fixture would seemingly do the same job as an 'Aquarium" fixture for 1/4 the price? (besides the fancy cover and design)
I feel like an idiot for not being able to pick up on the obvious disconnect that I am having...
My last question is; what is really more important? Watts per Gallon or Lumens per Gallon? Intuitively, I would say Lumens are. However, with a fixture directly over a tank (practically an 1" or less from the aquarium top) are Lumens particularily important as all of the effective light is being focused anyways, or is the W/G rule just another rule-of-thumb that gets us in the ball-park? <-Understanding that Lumens and focus are critical for fixtures elivated above the tank as radiant (or lost light), as well as distance, are big factors in these styles.
This last point may be the missing 'link' as to why seemingly identical outputs vary so greatly in price as I recall most (if not all) were pictured elivated...hmm.
Thanks in advance!
CT-Death
EDIT:
90G Tank lightly planted with -- Java Fern, Moss & Lace, and Vals and Swords (wishing for a medium planted tank not requiring too much in regards to ferts/CO2, but not afraid to either).