lighting obsession sounds like rubbish to me

I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.

I scuba dive, and I've regularly seen photosynthetic corals in 70 feet
of water. mind you, the water is very very clear in these dive sites,
but does 1/4" of glass really change the light spectrum more than 70
feet of water?

I mean this as a serious query, because I honestly don't know. I lean
towards a glass hood to limit evaporation (although if temperature reg.
is a problem, off it goes) but I'd like to hear why a glass hood is
bad.

__
Fjord

"Fjord" wrote in message
oups.com...
I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.


Trade-offs. Personal pref. The loss of some light, or evaporation and
jumping fish. Your choice, really. As stated when you asked almost
the same question 17 minutes before, you can lose up to 30% if
there's salt\dirt on the cover.

billy

"Fjord" wrote on 21 Aug 2005 23:0:
I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.

Here's a recent article:
http://www.advancedaquarist.com/2005/8/aafeature
that shows (among other things) what happens to the wavelengths of the
sun's light at different water depths, and how that compares with different
artificial "full spectrum" lights.

-- Don
__________________________________________________ _____________________________
Don Geddis http://reef.geddis.org/
University President: "Why is it that you physicists always require so much
expensive equipment? Now the Department of Mathematics requires nothing but
money for paper, pencils, and erasers...and the Department of Philosophy is
better still. It doesn't even ask for erasers." -- [Told by Isaac Asimov]

"Don Geddis" wrote in message
...
"Fjord" wrote on 21 Aug 2005 23:0:
I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.

Here's a recent article:
http://www.advancedaquarist.com/2005/8/aafeature
that shows (among other things) what happens to the wavelengths of the
sun's light at different water depths, and how that compares with
different
artificial "full spectrum" lights.

Excellent article. Something else perhaps worthy of consideration is that
the discussion and results only pertain to the light spectrum of 400-700 nm,
(the so-called photosynthetic active region, PAR). Metabolic processes
(vitamin absorption, melatonin generation, etc) in land-based critters cover
a vast range of the light spectrum, and tinkering with that process is cause
for lots of issues. I know next to nothing yet about the photo-metabolic
processes of aquatic life, but I would imagine that there is business going
on underwater with light of wavelengths other than those measured by the
author (water is a very strong filter of shorter wavelengths, though, so I
can't see the UV portion of the spectrum as being to highly critical to
aquatic life residing at any depth)...

In the spirit of trying to provide your tank-dwellers with
as-close-to-their-natural-conditions as possible, a glass cover would seem
to me to take you in a direction away from that goal. Granted, your living
room windows do the same thing, (with your hood putting light back into the
system) but I won't compromise those for the benefit of my aquarium,
especially not in New England with yet another cold winter on the horizon...
:-)

Regards
DaveZ
Atom Weaver

Evaporation is your friend, because it allows your tank to cool cheaply.
Topping off with fresh water is simple, and if you need help you can
set up an auto-top off system to keep up with that.

If you are worried about jumpers, put eggcrate (lighting diffusers) on
top of the tank. The grid will help keep the livestock in the tank but
avoid blocking the light nor trapping heat.

Fjord wrote:
I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.

I scuba dive, and I've regularly seen photosynthetic corals in 70 feet
of water. mind you, the water is very very clear in these dive sites,
but does 1/4" of glass really change the light spectrum more than 70
feet of water?

I mean this as a serious query, because I honestly don't know. I lean
towards a glass hood to limit evaporation (although if temperature reg.
is a problem, off it goes) but I'd like to hear why a glass hood is
bad.

__
Fjord


--
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Business Page: http://www.sparklingfloorservice.com
Marine Hobbyist: http://www.melevsreef.com

Contains heat in the tank, with small bodies of water you need evaporation
to cool the water, the light requirements of keeping corals demands actions
to keep tank temps reasonable. Plus there is some oxygenation if you keep
the surface agitated, and gas transfer. But the biggie is the heat and
needed
evap.

But with a skimmer (bubbles) and enough distance of light source (temp
transfer)
you can keep a lid. And sometimes a lid is needed like with octopus and
some fish.

But most reef tanks with light demanding corals we are always fighting
to keep
temps in line and evap is an easy way to help this issue.

Fjord wrote:

I'm setting up my first nano-reef. I'm reading some debates on
lighting, especially whether or not to use a glass hood. A common
concern I've heard is that glass will limit the transmittance of
certain wavelengths of light to the detriment of coral growth.

I scuba dive, and I've regularly seen photosynthetic corals in 70 feet
of water. mind you, the water is very very clear in these dive sites,
but does 1/4" of glass really change the light spectrum more than 70
feet of water?

I mean this as a serious query, because I honestly don't know. I lean
towards a glass hood to limit evaporation (although if temperature reg.
is a problem, off it goes) but I'd like to hear why a glass hood is
bad.

__
Fjord




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