incandecent, fuorscent, and wattage, physics

v3x10e8

Medium Fish
Oct 22, 2002
79
0
0
#1
time to start up a new thread.... *laughingcryingsmiley*
for incandecent and fuorscent light of the same voltage, i have the understanding that fuorscent light performs many times better, since incandecent light wastes most of the energy as heat (entrophy, anyone? yes, your light bulb has help in pushing the time arrow forward) -- 90%, in fact.  However, understanding physics does not help me in understanding the practicals of plant keeping.  
So here is my question:
by wattage reading of the bulb, does the wattage measure the light bulbs (incandecent / fuorscent alike) output ( watt /per meter^2 ) or the electric intake ( power = voltage * current)?
and how much better is a fuorscent than that of incandecent?
 

colesea

Superstar Fish
Oct 22, 2002
1,612
0
0
NY USA
#2
HEY! I JUST FINISHED READING THAT! About the only thing I got out of it was what I already knew: the entropy of this world is steadily increasing, and pretty soon, all heck will break loose<G>

Anyway, hmmm...I don't know exactly what the wattage of a lightbulb means except perhaps as output because on an incandescent bulb, you get greater output from a 60watt bulb than you do from a 40watt bulb (all the more light to read by<G>).

In fluorscents, I always look as spectrum as compared to wattage.  A blue spectrum bulb is not going to "look" as bright as a full spectrum bulb, even if they are at the same wattage.  Yet their output would be the same.  

I don't know about comparing incandescents with Flourescents. I think that is apples and oranges. Flourescents seemed to be more effecient in converting their energy usage into light instead of heat, so that will save the electric bill some. The standard for plant keeping, I believe is 2 watts per gallon, doesn't matter flourescent, incandescent, metal halide, or whatever you decide to use. You just have to take into account the depth of your tank and how much light penetration you need.
~~Colesea
 

v3x10e8

Medium Fish
Oct 22, 2002
79
0
0
#3
"doesn't matter flourescent, incandescent, metal halide, or whatever you decide to use."
if what you said is true, than the output  (total energy emitted via light ....... in a second), is what is measured, which seems to be more likely.  
i guess the spectrum matters too, as you said, since plants reflect green lights.
thankz for all ur help
happy fish keeping.
*thumbsupsmiley*
 

Oct 22, 2002
15
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0
#4
Actually the 2 watts per gallon rule does not apply to incandescents. Incandescents are absolutely useless for any serious plant keeper, they produce too much heat, the wrong spectrum, very inefficient in power use.
The wattage is a measure of how much electricity the bulb is drawing. It does not REALLY reflect how much light is being put out, but generally when comparing similar lights (flourescents) the more watts the higher the light output. Anyhoo, 2 watts per gallon of flourescent light is the general rule.
 

Matt Nace

Superstar Fish
Oct 22, 2002
1,470
1
38
Pennsylvania
#5
Watts is watts of power used.

You may need(want) a different light for different needs.All have differnt Lumens(the measure of all the light which exits from the bulb in all directions at the surface of light)

Like said, incandecents are not the primary choice. They run hot, and produce more of a beam of light. There are , however, full spectrum and plant lights available. I purchased two 65 watt plant bulbs, and they did good over the one plant they hit each...yeah one plant.

Fluorescents are a very cool, energy saver light. Very cheap to buy and operate. The problem with these are, they lose their punch into the water, the deeper the tank. An example is in my 55 gallon, (160 watts)where I found them useless compared to The Power compacts I have now.

Power compacts are a a kind of high output light. I am not sure what the depth and power of the light on the normal full length strips, but the utilty light I have is very strong, and clearly reaches the bottom of the 55 gallon. It only uses 65 watts, but produces a higher light in lumens than all my 160 watts combined, it just isn't as long, so more than one is needed.

Metal halide lamps are clearly a superior light in light output. One metal halide could light a 90 gallon tank no problem. Reflectors added can cast the light out better to cast it down where you want it.
 They cost a lot, cost alot to run, and cost a lot in replacments, and run very,very hot. MY friend has had the same bulb over 4 years however, and he says it is still super bright. I suppose these don't dim, but just burn out.

VHO(Very high output) is another fluorecent. It has a strong lumen, but runs very Hot. The ballast are expensive, the lights are not exactly cheap.

Mercury vapor is another good light, but runs very hot. Produces kind of a wide beam, and I think PC and halides are better for their price.