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Re: lighting a 29 gallon

john wheeler wrote:
> I think you answered your own question. A 55w PC setup
> from AH supply is roughly equivalent to 82.5w of
> normal output flourescent lighting. Not much you
> *can't* grow with that.

If you don't mind me asking, how did you arrive at that figure? I have
been hunting high and low for information about the light output of PC
bulbs w/reflectors vs. NO bulbs and how that relates to the "watts per
gallon" rule.

Right now I am in the process of building up an 80g tank and have two AH
Supply 55W PC fixtures in it. I also have a 29g with 2 24" NO bulbs. I
have no way other than a digital camera to measure the light output. I
tried putting a white plate on the substrate of each tank and comparing
the camera's exposure time with same f-stop and ISO. When I attempted
this, the 29g tank wanted 1/5th of a second exposure, and the 80g wanted
1/25th. I don't think that the AH Supply bulbs are so powerful that they
can put out that much *MORE* light. There is 7.85W/sq. in. in the 80g,
and 9.75W/sq. in. in the 29g, yet the actual light striking an equal
area on the substrate is 5 times more in the 80g? Didn't sound right to

Thanks in advance for any information you can give.

Jerry Baker