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July 28th 05, 04:40 PM
Hello all,

I'm building out a reef tank and after reading several posts and books
it seems the two biggest issues are nutrient export and lighting.

I've recently stumbled across a new company that is offering something
called sunlight direct. Essentially it is a dish that one mounts
outside that collects lights and feeds it inside your home via fiber
optic cables. It's essentially a solar collector.

In their words the idea is to "To capture sunlight and distribute it,
using optical fibers, into the interior of a building to provide
premium quality, controllable lighting capable of reducing energy
consumption."

Their website is http://www.sunlight-direct.com/overview.html. Does
anyone see a problem with this idea? The downside is that during the
winter months (at least in the US anyway) the hours during which the
sun will be up and the time during which I'm home doesn't coincide as
much as I would like but I hear that fish (and really all animals)
become healthier under the sun.

Any thoughts?

George Pontis
July 28th 05, 08:09 PM
In article . com>,
says...
> ...
>
> Their website is http://www.sunlight-direct.com/overview.html. Does
> anyone see a problem with this idea? The downside is that during the
> winter months (at least in the US anyway) the hours during which the
> sun will be up and the time during which I'm home doesn't coincide as
> much as I would like but I hear that fish (and really all animals)
> become healthier under the sun.
>
> Any thoughts?

The web site says:

"special optics that allow only visible light to be concentrated "

I don't know what sort of filters they use but possibly some of the shorter
wavelength light that is sought by the marine aquarists would be lost. So that is
a possible issue, I don't know for sure. I wonder how it is on cost ? If
reasonable, it seems like a good idea and worth trying. There would be a nice
energy savings if it could even reduce the lighting requirements by half.

There is another, lower tech device that could provide some useful sunlight. It is
a skylight attached to a shiny, metallized flexible tube. In the right setting it
could be easy enough to install. The sunlight-direct product is probably easier to
integrate with electric lighting.

Don Geddis
July 29th 05, 05:13 PM
> In article . com>, says...
>> Their website is http://www.sunlight-direct.com/overview.html.

George Pontis > wrote on Thu, 28 Jul 2005:
> I wonder how it is on cost ? If reasonable, it seems like a good idea and
> worth trying. There would be a nice energy savings if it could even reduce
> the lighting requirements by half.

Their web site admits that it is very expensive. Isn't even a commercial
product yet. And the first version is only for businesses; the home product
won't come until a few years from now.

> There is another, lower tech device that could provide some useful
> sunlight. It is a skylight attached to a shiny, metallized flexible
> tube. In the right setting it could be easy enough to install. The
> sunlight-direct product is probably easier to integrate with electric
> lighting.

I looked at this one in the past. Only transmits a tiny fraction of the
sun's intensity. It's nice to lighten up a dark corner of a house, but there
probably isn't nearly enough energy transmitted to grow corals.

-- Don
__________________________________________________ _____________________________
Don Geddis http://reef.geddis.org/
Q: What happens if you play blues music backwards?
A: Your wife returns to you, your dog comes back to life, and you get out of
prison.

Tre' Landrum
August 13th 05, 04:23 AM
Another problem with plumbing in direct sunlight is that the wavelengths the
corals we like are not the suns full wavelength. Most corals are from a fair
distance under the water. It only takes a few feet of water to start
filtering out the reds, and the deeper you go the more you only have blue
left. That is why when we are trying to grow corals from 40 foot of water we
want 10K & 20K light... aka blue light. If you just pump full spectrum sun
light you will have a light that is about 2400K.... aka perfect for growing
plants.. not as good for growing coral. Sorry to burst that bubble.

Tre' Landrum


"Don Geddis" > wrote in message
...
>> In article . com>,
>> says...
>>> Their website is http://www.sunlight-direct.com/overview.html.
>
> George Pontis > wrote on Thu, 28 Jul 2005:
>> I wonder how it is on cost ? If reasonable, it seems like a good idea and
>> worth trying. There would be a nice energy savings if it could even
>> reduce
>> the lighting requirements by half.
>
> Their web site admits that it is very expensive. Isn't even a commercial
> product yet. And the first version is only for businesses; the home
> product
> won't come until a few years from now.
>
>> There is another, lower tech device that could provide some useful
>> sunlight. It is a skylight attached to a shiny, metallized flexible
>> tube. In the right setting it could be easy enough to install. The
>> sunlight-direct product is probably easier to integrate with electric
>> lighting.
>
> I looked at this one in the past. Only transmits a tiny fraction of the
> sun's intensity. It's nice to lighten up a dark corner of a house, but
> there
> probably isn't nearly enough energy transmitted to grow corals.
>
> -- Don
> __________________________________________________ _____________________________
> Don Geddis
> http://reef.geddis.org/
> Q: What happens if you play blues music backwards?
> A: Your wife returns to you, your dog comes back to life, and you get out
> of
> prison.

Don Geddis
August 14th 05, 12:53 AM
"Tre' Landrum" > wrote on Fri, 12 Aug 2005:
> Another problem with plumbing in direct sunlight is that the wavelengths the
> corals we like are not the suns full wavelength. Most corals are from a fair
> distance under the water. It only takes a few feet of water to start
> filtering out the reds, and the deeper you go the more you only have blue
> left. That is why when we are trying to grow corals from 40 foot of water we
> want 10K & 20K light... aka blue light.

OK, true, you need enough energy in the blue spectrum.

> If you just pump full spectrum sun light you will have a light that is
> about 2400K.... aka perfect for growing plants.. not as good for growing
> coral. Sorry to burst that bubble.

I'm not so sure this is a problem. Direct (shallow) sun light may have an
"average" temperature of 2400K, but surely it has all the blues also. The
reason we worry about the 10K and 20K lamps is because artificial lights tend
to have very narrow spectrums, and you need enough blue in there to stimulate
the coral growth.

But I've seen no evidence that direct sunlight would be a problem, even with
corals from 40' of water. Do you have some reason to believe that they would
fail to thrive under (shallow) sunlight? What do you think goes wrong?

-- Don
__________________________________________________ _____________________________
Don Geddis http://reef.geddis.org/
To me, death is like a doorway. And getting knocked out is like one of those
pet doors. And sleep is like a little mouse hole.
-- Deep Thoughts, by Jack Handey [1999]

kim gross
August 14th 05, 04:53 AM
Tre' Landrum wrote:
> Another problem with plumbing in direct sunlight is that the wavelengths the
> corals we like are not the suns full wavelength. Most corals are from a fair
> distance under the water. It only takes a few feet of water to start
> filtering out the reds, and the deeper you go the more you only have blue
> left. That is why when we are trying to grow corals from 40 foot of water we
> want 10K & 20K light... aka blue light. If you just pump full spectrum sun
> light you will have a light that is about 2400K.... aka perfect for growing
> plants.. not as good for growing coral. Sorry to burst that bubble.
>
> Tre' Landrum
>


This is not true at all. First most of the corals that are collected in
our hobby come from less than 20 feet of depth. Second, sunlight is not
2400K it is aprox 6000K color temp. Natural sunlight is one of the
best ways to grow corals. If you look at just about any successful
coral farm they use natural sunlight for the majority of thier light
needs. Plus most corals will grow well even in light as with a color
temp as low as 5000K or even 4500K, now the color might not look the
same as it would in a tank with 20,000K bulbs on it, but it will grow a
lot faster.

Kim

Boomer
August 15th 05, 01:42 AM
As Kim has said more like 20 feet or so and the Kt at such a depth is nowhere near 20K or
even 15K but more like 10 K, so the water is a blue/green color

--
Boomer

Want to talk chemistry ? The Reef Chemistry Forum
http://www.reefcentral.com/vbulletin/index.php


Former US Army Bomb Technician (EOD)
Member; IABTI, NATEODA, WEODF, ISEE & IPS

If You See Me Running You Better Catch-Up


"kim gross" > wrote in message
...
: Tre' Landrum wrote:
: > Another problem with plumbing in direct sunlight is that the wavelengths the
: > corals we like are not the suns full wavelength. Most corals are from a fair
: > distance under the water. It only takes a few feet of water to start
: > filtering out the reds, and the deeper you go the more you only have blue
: > left. That is why when we are trying to grow corals from 40 foot of water we
: > want 10K & 20K light... aka blue light. If you just pump full spectrum sun
: > light you will have a light that is about 2400K.... aka perfect for growing
: > plants.. not as good for growing coral. Sorry to burst that bubble.
: >
: > Tre' Landrum
: >
:
:
: This is not true at all. First most of the corals that are collected in
: our hobby come from less than 20 feet of depth. Second, sunlight is not
: 2400K it is aprox 6000K color temp. Natural sunlight is one of the
: best ways to grow corals. If you look at just about any successful
: coral farm they use natural sunlight for the majority of thier light
: needs. Plus most corals will grow well even in light as with a color
: temp as low as 5000K or even 4500K, now the color might not look the
: same as it would in a tank with 20,000K bulbs on it, but it will grow a
: lot faster.
:
: Kim