Re: NANFA-- 135 gal. Freshwater Tank
Sun, 1 Feb 2004 20:05:39 EST

In a message dated 2/1/04 3:08:38 PM Eastern Standard Time, writes:

> Martin raises a good point about light below. The lights in the hoods I
> are indeed actinics, with each hood holding a pair of the following: Osram
> 36 W, 2900 lumen Daylight; and Power Compact 36 W, 460 nm Blue. with (I
> think?) more lumens. Like I said before, I've never fooled with this type
> gear but I know there's always extensive debate on lights in various
> Martin said he didn't think actinics would provide enough phytoreactive
> light. But I would think that a source of 460 nm light would be exactly
> right, since that's the range where blue shades into green, and I know
> various aquatic photosynthetic pigments have reaction peaks in that range.
> Any opinions based on this more exact info?
Actually actinic light is directed at marine symbiotic algae's which have a
different ratio of light frequency needs than the higher plants we keep in our
aquariums. In higher plants red light is more important than blue. 460
nanometers is closer to where blue light shades into violet than blue into green. I
used to grow live coral and stuff like that. The reason for the blue spectrum
in salt water is that deep under water red light is filtered out first by the
marine water column and blue last. If you cut your self underwater below about
30 feet the blood looks green instead of red because there isn't any red light
for your eye to see with. The algae that live in coral has brown pigments
which absorb blue light better than red. Only Red algae really use green light

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