[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Illumination

Greetings to you all:
     I would like to say thank you for all the responses I got to my
previous listings.  I am trying to educate myself on the subject of lighting
for aquarium plants.  I have learned much but when it comes right down to
purchasing time, I remain puzzled.  We refer to the necessary measure and
quality of light in many terms and units. I do not feel competent when it
comes time to buy a simple light bulb or tube.  Light is refered to in units
of: 
lumens,
degrees Kelvin,
watts.
light spectrum in terms of color, 
lux,
and then there are differing lights such as florescents, incandenscents,
metal halide, mercury vapor and more.  What a jungle!
     Someone informed me that the "degrees kelvin" was a reference to light
spectrum or color spectrum.  All I know is that I need primarily a good
spike in the blue and red part of the spectrum when I see the data graphed. 
But not all light packaging provides this graph or a measure of the
frequencies of the color spikes I need.  Is pure white light any good? 
White light should have it all or is that not correct?
     Now there is the problem of intensity.  My tank is 21 inches deep and
actually holds 26 gals, and not the 30 gal tall they market it as being.  I
need to know if I want watts, lumens, or lux.  Perhaps even some other unit
of measure.  Or, better yet, I could use some formulas to convert from one
to the other, because the different lines of available light use different
units of measure, and different markets will refer to differing units of
measure.  The tubes sold by Hagen USA have the data listed in lux, lumen,
kelvin and watts!?
     My college physics book wasn't much help to me.  Where is such data to
be found that it can be put to good use.  For all that I think I know I just
don't seem to know what it takes to purchase the best lighting.  I am
looking at all options.  I have called hydroponics sales people and light
companies.  I want to understand it well enough to be able to begin asking
the right questions so I can make the best choices.
     I found one company that sells a meter to measure the light intensity
underwater.  But that meter is not cheap nor do I believe it is necessary
for my needs. Judging from all the questions I see about lights and lighting
in this group, I think we could all benefit from some help.  I am not really
looking for brand name knowledge and marketing labels here, as much as how
to look at the packaging labels and be able to make basic determinations to
what lights would be possible candidates for consideration in use for
aquatic plants verses other uses.  I hope I don't need to become an optics
or physics major to understand this either.  I fear I may be opening a can
of worms.  I do know, however that we have some great expertise and
knowledge that is shared in this group.  I look forward to your help and
wisdom gained over years of experience.
Thanks, Diana  





_______________________________________________________
Get 100% FREE Internet Access powered by Excite
Visit http://freelane.excite.com/freeisp