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Can someone please give me some basic info on lighting for planted tanks? True actinic, T8, 10000K, 50/50 VHO...I'm lost :%) I don't need anything fancy, I'm just looking for decent lighting for planted tanks.

Also, flourescents like [link=these]http://www.bigalsonline.com/catalog/product.xml?product_id=23441;category_id=1845;pcid1=1843;pcid2=" style="COLOR: #FF66FF[/link] are listed as 10 watts. Am I then correct in assuming that gives me 20 watts of lighting?

Sorry if these are silly questions.



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There is water at the bottom of the ocean

Not silly questions at all. with all the options today for simple lighting today its a wonder anyone bothers to ask.

what size tank is this for? any plants? if so what kind?
what effect are you going for, looking for a heavy blue or subdued sunshine?

I'm actually shopping for a few tanks...my 30, 29, a 10 and possibly my 20 long

The tanks are all planted...swords, crypts, anacharis, java fern, anubias, dwarf sag.

I'm not sure about what effect, probably leaning more towards sunshine than blue though.

~~~~~~~~~~~~
There is water at the bottom of the ocean

Hi,
This could be a long reply, so grab a cup of coffee, or
a soda pop, sit back and enjoy.

The mysteries of aquarium lighting... Let's see if we
can't help.

First, the only real "NO" is don't use incandescent light
bulbs. They burn a lot of electricity, give off large
amounts of heat, and the light they emit is not good for
plants.

So, where does that leave you?
Several options:

The first is flourscent lighting.

(In a nutshell..)
Flourscent lights are glass tubes lined inside with
phosphors (rare earths) that glow when excited by electrons
(electricity. There are tiny filaments connected to the
pins on the ends of the tubes, and when the switch is
turned on, current flows from a transformer (called a
ballast) to the filaments they glow and the heat excites
the gas and electrons flow striking the phosphors and
they in turn give off light.
The phosphors in the tubes determine if they are plant
bulbs, reading bulbs, or for other purposes.
Flourscents come in various lengths, and "sizes."
They are available in T-12, T-8, and T-5 diameters.
T-12's are 1 1/2 inches in diameter.
T-8's are 1 inch in diameter.
T-5's are 5/8s inch in diameter.
Generally, the T-12's and T-8's are 40 watts or less per
tube. The T-5's are classed as High Output (HO). This is
because they are only 5/8 inch in diameter and put out
lots of light for something so small (thin). T-5s can
be as low as 4 watts, and up to as high as 48 watts.

Another is:
Very High Output (VHO) flourscents are lights that are
made to run at higher voltages, and thus require special
ballasts, and wiring including the end caps (sockets) for
the bulbs. They are T-12 bulbs, and come in wattages up
to 160 watts. VHO's generate some heat, and generally have
a fan mounted in the canopy to carry off the heat from the
bulb and from the tank.

Another is:
Compact Flourscent Bulbs.
These are bulbs that are thin like the T-5's but instead
of being one long bulb, they are in the shape of a tight
"U." They come in two types, determined by their base
where it plugs into the socket. Some have 4 pins in the
shape of a square, and others come with 4 pins in a straight
line. Compacts generate some heat, and nearly all have
fans built into the canopy to carry the heat away from the
bulb(s) and from the tank. Compacts come in 18,32,40,65,and
96 watt sizes.

Another is:
metal Halide bulbs,
These are almost flood lights. They are extremely bright
lights, all incandescent style and are designed to emit
lots of concentrated light within the demands of Salt Water
tanks. They generate tremendous amounts of heat, and are
nearly all mounted above the tanks and shine down into them.

Next:
Along with the types (normal T-12, T-8) and HO (T-5) and
VHO, and Compact Flourscent bulbs, you also have a rating
that is called the "Kelvin rating."
To get an idea what the Kelvin rating is, you would have
to take a piece of black metal and heat it with a torch.
The metal will start to glow red then yellow, then white,
then blue as the temperature got increasingly hotter.

Our sun is rated (roughly) at 6700K At 10,000K and above
the light changes from white to progressivly bluer in color.
Plants prefer light in the red and blue parts of the light
spectum. However, we humans prefer the light between the
two. Red light only penetrates into the water colum a
small amount, while blue light penetrates dozens of feet.
So called Plant grow lights, generally combine the
two spikes and give off a pink or purplish light.
Light in the 5000K range tends to be a yellowish red and
kind of "dim" looking and tends to "wash out" the colors
of the fish and plants. Light from 10,000K and up tends
to shift from the very bright white into the bluish colors
and this too (especially the 20,000K and Actinics) tends
to washout the plant colors.
Generally speaking lights above 10,000K are used in salt
water tanks that house corals and other invertebrates.
They need the intense bright light to manufacture the
chemicals and algae necessary for life and their colors.

So, what kind of light would work on your tank?

If it is less than 20 inches deep, you can choose any
flourscent (normal, HO, VHO, Compact) that you can afford
and that will fit atop your tank. If you choose a
regular flourscent bulb hood (T-12, T-8), purchase the
bulb at your local hardware store and save money.
Purchase a bulb that says DAYLIGHT, or SUNLIGHT.
Those give off light in the 6700K range, ideal for
humans and plants. Don't...purchase the "Warm" series
(Warm White, or Soft White) these are designed for reading
and don't have the "glare" of sunlight.

If your tank is over 20 inches deep, then the red part of
the spectrum will be scattered and absorbed by the water
and floating debris in the water, and you would want to
use a mixture of the 6700K and a 10,000K bulbs to penetrate
through the water to the substrate

If your tank is small, 10G or less, purchase the screw
in compact flourscent bulbs. These, combined with the
tanks shallow depth will give you all the light you need
for nearly any plant.

How much power (watts) you need should be determined by
the plants that you keep. If your plants are low light
plants then keep the wattage around 1 watt per gallon.
If you are keeping medium light plants, then you will want
more than one tube and you should shoot for 2 watts per
gallon. If you are going to keep high light demand plants
then you want to have over 3 watts per gallon and will
probably want to use the Compact, or VHO or HO bulbs.

To determine how much power you have, take the total wattage
of the bulb(s) and then divide that by the capacity of the
tank. For instance, a 55G tank with a single flourscent
T-12 bulb is 40 watts. Divide 40 by 55 and you get .7 watts.
Thats good for looking at the fish, but really pushing the
lower limits of low light demand plants. Chances are you
will not be successfull with that setup. You'd need to use
a two bulb canopy (80 watts divided by 55 = 1.4 (nearly 1.5)
watts per gallong (wpg) and would be able to grow the low
light plants.

This is the "nut shell" version. There is lots more theory,
and practical information as well, but that might overload
your basic question.

Hope this helps...
Frank


Last edited by FRANK at 08-Apr-2005 17:40

Last edited by FRANK at 08-Apr-2005 17:44

Last edited by FRANK at 08-Apr-2005 17:46

-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

Blue light isn't always bad. It can wash out plant colors but I like the softer dimmer light on my 55g and it brings out some fish colors better.
Here's my giant lilly from some unknown walmart bulb and congo tetras under 40w of 10,000k and 40w of actinic(18,000k), reg flourescent:

Very bright colors on the congos. I couldn't even get pics of them under that light. They are just streaks of color.

The new 220w compact flourescent with 110 in 10,000k and 110 in actinic:
[link=http://img.photobucket.com/albums/v634/sham885/lighting/P1010227.jpg]http://img.photobucket.com/albums/v634/sham885/lighting/P1010227.jpg" style="COLOR: #00C0C0[/link]

I don't have pics of it under the old lower kelvin lighting but I have some with flash that looks similar. It does throw some of a glare but under the original lighting the congos blue barely showed and the red was much more faded. The plant colors are sharper though.
[link=http://img.photobucket.com/albums/v634/sham885/lighting/P1010260.jpg]http://img.photobucket.com/albums/v634/sham885/lighting/P1010260.jpg" style="COLOR: #00C0C0[/link]

And this pic where I think I turned out all the tank lights. The bulbs in the room light are 67000k daylight bulbs.
[link=http://img.photobucket.com/albums/v634/sham885/lighting/P1010260.jpg]http://img.photobucket.com/albums/v634/sham885/lighting/P1010260.jpg" style="COLOR: #00C0C0[/link]

My 20g has 6700k bulbs and I don't like it. It looks somewhat yellow to me but then I have my 55g right across the room as comparison.[/font][/font][/font]

Just as a side note on franks post.
I've found that 65000K daylight bulbs not only the easiest to hunt down (I get my bulbs from home depot) but also the ones that give the best color to both fish and plants.

^_^


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