Kelvins?

[Jer-]

Hi

What is Kelvin? What is the relationship between healthy plant life and Kelvin? how many kelvin do i need for healthy plant growth provided i hav a CO2 system goin on.

Thanks

 

[The Mohave Kid]

"What is Kelvin?"

Kelvin is a temperature scale .. like Celsius or Fahrenheit. Water freezes at 0 degress celsius .. 273 degrees Kelvin and 32 degrees fahrenheit.

"What is the relationship between healthy plant life and Kelvin? "

The color or colors of light emitting from a source or it's "color temperature" is sometimes described in degrees kelvin. During the day for example the color temperature changes ... afternoon 55OO Kelvin (K) ... morning light .. like sunrise 3200 K ect.. Light energy is absorbed by plants and used to power photosynthesis ... some colors are more useable or harvestable then others .. red and blue are very important but plants can make use of other colors as well and by no means are these the only colors that are absorbed by a plant. Given this information one may select a lighting set up that has a color temperature best matched to the plants they are attempting to grow in the aquarium.

What is really more important is the color and quantity of light falling on a leafs surface ( not emiiting from the source ) since the color and the amount of energy contained in light emitting from a source will decrease or change significantly as it enters and moves deeper into the aquarium.

I will let someone else suggest what color temperature is best to start with and how much power or watts your light system should have for a given tank since I myself am new to growing plants in a aquarium.

I'm still out to lunch on the benafits of CO2 in the aquarium ...

Good Day ... B)

 

[Aulonochromis]

Anything from 2700k to 10,000k can be used for plants. K ratings aren't very accurate as 2 different lights with the same K rating can have very different spectral curves.
I use have 2 different brands of 10,00K bulbs over my tank. One is pink, the other is blueish white. Here's a good link. http/www.aquabotanic.com/lightcompare.htm

 

[Mr Miagi]

"What is Kelvin?"

Kelvin is a temperature scale .. like Celsius or Fahrenheit. Water freezes at 0 degress celsius .. 273 degrees Kelvin and 32 degrees fahrenheit.

He is right, but he is wrong. Kelvin is another way to tell the temperature really.

Most people made thermometres that could only go to 0 because they thought that was the freezing point of water. IT IS, but water can be cooled down to -273 degrees C. So they made the Kelvin scale for scientists who needed a much more accurate scale. So he was right in that it is a nother way of measuring temps. But he is wrong that -273K is NOT the freezing point of water.

 

[Jer-]

Oh ok thanx.

I am going to buy a light for my tank today, its already got one buy i want something brighter. Is getting any old kinda lamp ok? as long as its extremely bright? (or as long as the wattage is enough, ie 1.5watts per L)

 

[The Mohave Kid]

Mr. Miagi ..

"but water can be cooled down to -273 degrees C."

Sure it can but this is NOT the freezing point of water but a different concept called absolute zero ...

I think your a bit confused ... there is nothing more accurate about kelvin versus Celsius ... Water freezes at 273 K ... in degrees Celsius thats 0 C in fahrenheit 32 degrees ?

"Absolute" zero is where all molecules stop moving or are at their lowest possible energy state and this is happens at 0 degrees K .. - 273 C or - 460 F .... all three temps are valid and just as accurate pick whatever one you like ... The kelvin scale simply lets scientist start at 0 instead of at - 273 or -460 .

"But he is wrong that -273K is NOT the freezing point of water. "

No ... I'm right ... -273 K is NOT the freezing point of water ( I think you meant - 273 C ) ... Water freezes long before absolute zero ??? ... They are two different concepts "freezing point" and "absolute zero" and they occurr at different temperatures. Molecules are still moving or vibrating in chemical bonds in frozen water .. but not at absolute zero. All substances can be cooled to absolute zero but all have different freezing points.

Hope that makes sense ... and is helpful.


Good Day ... B)

 

[NikkiY]

No ... I'm right ... -273 K is NOT the freezing point of water ... 0 K is absolute zero and so is - 273 C ... Water freezes long before absolute zero ??? ... They are two different concepts "freezing point" and "absolute zero" and they occurr at different temperatures. Molecules are still moving in frozen water .. but not at absolute zero. All substances can be cooled to absolute zero but all have different freezing points.

Hope that makes sense ...

Mohave kid is abolutely right. 0 K isn't the freezing point of water. Degree Kelvin is there because it is the temperature where all molecular activity of any matter stops. For the sake of convenient, scientists call this 0 K. Of course, degree Kelvin is named after some famous physist. As an engineer, I use any one of the temperature scales without as neccessary. All these are temperatures and they are equally useful and important.

Nikki

 

[Discomafia]

Best kelvin rating for plants is 5000 to 6700K... This is well documented on the forum, so just do a search and check for yourself. And you plan to get 1.5 watts per L or per gallon? Because 1.5 watts/litre is some serious light!!!

5.67 WPG is no joke, and is for the experienced aquarist only, with a fully planted setup. 1.5 WPG will do, but the general consesus is that once you reach 2 WPG, you'll be able to grow most plants, so try and aim for that if you can. Also what size tank do you have, as the wpg "rule" doesn't work for tanks smaller than 30 gallons. HTH.

 

[FrAnK3333]

You know what a good warm temp.? 0 kelvin, its only the temp. atoms seize to move.

 

[Jer-]

Discomafia, my tank is way less than 30 gal, it is only a 15 gal. What is the general rule for a 15 gal tank?

I hav a compact fluroscent light that is not bright enough, and today i went to an aquarium store and harware store, they both didnt hav any compact fluroscent lighting for sale, they only had normal fluroscent tubes. so i was wondering whether the energy saving bulbs will work? cos they look pretty much like compact fluroscent light. Are they pretty much the same as the compact flu lights?

can i use them to grow plants in my tank?

Thanks

 

[Jer-]

I am hoping to use the energy saving light bulbs that u can screw into a normal incadescent light bulb socket cos they are cheaper than having to buy a whole fluroscent tube set (the ballasts, i think they are called). Plus i hav 2 sets of the fluroscent light controllers back home in Australia, i jus dont wanna buy another set cos i am goin back home in 3 months.

Please, anyone, help me out, can i use the energy savin bulbs that is available everywhere. Is there a Kelvin Rating to that?

If u do not know wo tkinda light i am talkin bout then please visit
http/www.lightbulbs-direct.com/
the kinda light i am talkin bout is right underneath "Welcome to LightBulbs Direct!"

Thanks

 

[Discomafia]

Compact FLourescents are always good, I used these for a while, then switched over to these because of the suitable kelvin rating. Basically the kelvin rating shows the colour of the bulbs, and it gets blue as you go higher, like the marine bulbs are 20,000K for example, and that is the kelvin rating that mimics the ocean 20 feet under or something like that...

The first bulbs were brighter (more intensity/watts) but I changed over because they were only 2700K. Actually, intensity matters more than the kelvin rating, as I used to have good plant growth when I used the former bulb as well.

This was for my old 10G planted setup by the way...

 

[Mr Miagi]

DOH, reading back my post i didnt make any sense, sorry. It was a typo.

I knew the freezing point of water being zero, but the way i understood it was that once frozen, you could still cool ice down to -273. And that was why they made the Kelvin scale?

Thats kinda what i was trying to say in my poor english skills. )

Sorry if i mislead anyone....

 

[Silly me]

hi Jer- .. You can use any light you please as long as the Kelvin ( I'm sure you now know what it means) is over 5000K