2 WPG lighting. High, Low or Moderate?

don't forget that an AH supply fixture has much better efficiency than a regular fixture. I think it's like 35% better or something (it's on their site), so take that into consideration.
 
I just got my AH supply kit, (Same one as the OP) and it's BRIGHT!

Mgamer told me that with the 2X55 kit over my 55g tank, its med light. MG also set me up with a great package. Check out the classifieds if you haven't already
 
For the sake of clarification, I have the 2x55 compact fluorescent AH supply kit.
Andy

youre getting more light into that 55 with those reflectors, they are the best out there. plus its PC which is better than normal output. I think you are more in the medium light range with that amount of light plus a 55 gallon isnt that terribly tall. I would say you could grow most anything with maybe the exception of a few difficult red plants. Even more if you add co2 to your tank.
 
So should we then really measure wattage against the height of the tank instead of volume? Obviously if you only lit one side of the tank, that won't help on the other side but at least on the area where it is lit, sounds like water depth has more to do with the type of plants you can grow than the volume...
 
sure, compare a standard 20 long to say a 20 hex. if the tank is more shallow more light will penetrate to the bottom. I guess its more relevant for your bottom plants and ground cover plants.

the wpg rule is just a standard to go by, there are many variables that come into play. Reflectors, depth of tank, intensity of the fixture etc. Also when you get into tanks below 10 gallons and tanks over 75 gallons, the wpg rule is relevant.
 
This wpg sounds as rough as fish inches per gallon rule which is also not that accurate. At least for the stocking rule, you can do it a bit better by relating to the surface area of water. In this case, height seems to make sense to me.
 
"Plant" and "not a plant" are labels you'd be surprised to not see at my lfs.
 
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