"pyrite" wrote in message
news
In article ,
"Mort" wrote:

Hi all, I am pretty much a newb when it comes to lights.

I have 2 tanks that I want to redo the lighting for as I am unhappy with
what I have now.

in my 180 I am using 2 "Reef Sun" 50/50s. It's a combo of 6500K
trichromatic daylight phosphor and actinic 420 phosphor. Can someone
explain to me what this means?

The 6500k side has a color that is somewhere around evening daylight.
The actinic side produces virtually no light with a wavelength longer
than blue. Many marine organisms have adapted to a blue environment
since blue light penetrates a little deeper into the ocean.

Then, I have regular lights from home depot which are too yellow for my
taste. They are Phillips F30 Home light.

The Reef Suns are very blue which I think would be okay if the other
lights
werent so yellow. I want something more white. Blue/White is ok but I
dont
like this blue/yellow.

I dont have anything as of yet on the 90 gallon but I was gonna get
those
cheapy 7.29 fixtures from home depot...

They work. With a four foot four tube standard t-12 fixture you would
have 160 watts over the 90g tank. This is about 1.8 wpg, plenty of light
for many of the less fussy plant species but not enough to require you
use co2.

Also, is my understanding correct that the 6500k number is a
representaion
of the color? Like 10000-18000 is very blue where lower numbers are
yellow
and red?

The k number stands for degrees kelvin. It is the standard way to
describe the average frequency (color) of light or other electromagnetic
radiation. You are correct about the color temperature increasing as you
move up the spectrum towards blue. A cloudless blue sky is about 12000k,
an incandescent light buld may be as little as 4500k.

An important thing to remember is that the color temperature represents
the average frequency. Most light sources will provide light at a number
of frequencies. The distribution of them will affect your perception of
the light.

It may take a little trial and error but eventually you should be able
to find a lamp or combination of lamps both you and your plants find
pleasing.

--
First sniggle: Feb 13, 1996


Thanks for the help!

I remember seeing a web page that should the various colors at different
wavelengths but I am unable to find it now. Anyone have any ideas? Thanks!

~Mort