Fixtures

From: Barry Meyers-Rice (bamrice@ucdavis.edu)
Date: Mon Apr 13 1998 - 09:55:20 PDT


Date: Mon, 13 Apr 1998 09:55:20 -0700 (PDT)
From: Barry Meyers-Rice <bamrice@ucdavis.edu>
To: cp@opus.hpl.hp.com
Message-Id: <aabcdefg1234$foo@default>
Subject: Fixtures


> I have found a very good 100x40x30 cm aquarium for about US $ 45.
> It's time now to build the fixtures.
>
> We are following the advices given by Barry Meyers-Rice. The article
> is the best we have found so far on the subject, but if you read it

Thanks!

> carefuly, there are a few contradictions. About them, I invite you to
> share your experience.

Uh oh...

Jose, let me explain.

If I recall the inventory in my hardware stores correctly, it goes like
this. The interior coating of fluorescent bulbs determines the spectral
balance of each bulb. Bulbs with different spectral balances are given
different names, such as "cool-white," "warm-white", "full-spectrum," and
"grow-light" (this latter may be spelled something horrid like gro-lite).
Both grow-light and full-spectrum bulbs may be the very expensive bulbs I
recommend against in the FAQ. The less expensive cool-white do just fine
in my growing chambers.

Now restricting yourself to cool-whites, you can get them as 40W, 34W, and
25W. At the time I wrote that portion of the FAQ, I read numerous
pamphlets which said that 40W bulbs were being removed from the market,
and were being replaced by the 25W bulbs. If you wanted to use the new 34W
bulbs you had to use the new, Energy Saving Ballasts with them. Strangely,
now that I have moved to California I have seen some 40W bulbs in stores.
I don't know if these are old inventory being sold off?

> -Must I use fluorescent energy saving bulbs, or is it OK to use
> simple cool-white incandescent bulbs? Anyway, from the point of view

Incandescent bulbs, no matter how you make them, produce *far* too much
waste energy as heat. You will need to contend with a cooling system if
you use incandescent bulbs.

> -There is another alternative, using in total, 2 fluorescent tubes,
> 4' long in one single 4' long fixture. This fixture would be made out

You will not get much light from just two bulbs. I use four to six in all
my terraria.

I don't know what to say regarding the 220V/110V problem. I don't know
what you are trying to calculate when you multiply Watts by volts. It has
been a while since I got my physics bachelor's degree, but Power (watts)
is calculated by

P=I*V=V*V/R, where P=Power, V=Volts (rms), and R=resistance. This should
all be avoided in this argument though, and you should try to find the
lumens power output of the bulbs and stick with that.

I wish I could help you more in Chile, but I don't know what kind of
lights you have. I am surprised that the most power producing bulbs you
can get are only 15W!

Keep me posted on your work! Good luck

Barry

---------------------
Dr. Barry Meyers-Rice
Carnivorous Plant FAQ
http://www.indirect.com/www/bazza/cps/faq/faq.html



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