# will a 6500k bulb seem brighter than 5000k?



## The Baron (Jul 9, 2010)

AS title says, I have an 18" 15 watt marinleand natural daylight which I belive is rated at 5000K and has a definate yellowish tint to it.

Will a bulb rated at 6500k or higher "appear" brighter to the eye?

Dont want to buy new bulbs if it wont be brighter.

BTW, the bulbs are only 2 months old.

Thanks,

Dan


----------



## xmas_one (Feb 5, 2010)

Apparent color temperature and perceived brightness are not related. The 6500K should appear more "crisp" and less yellow than the 5000K you currently have. Also bear in mind that bulbs with high PAR aren't always the "brightest" either. 

http://en.wikipedia.org/wiki/Photosynthetically_active_radiation


----------



## The Baron (Jul 9, 2010)

I kinda figured that. 

I; trying to bring out the blues more in my rams and this bulb is not
helping. 
I do have low light plants btw so I dont want actinic...
WOuld 10000K bulbs enhance the blues and still allow plant growth and appear "brighter than 5000K?

Any way for me to find out what bulbs have the highest lumens? 

Thanks,


Dan


----------



## Jane of Upton (Apr 2, 2006)

Hi,

I don't think actinic or 10,000 K lamps do much for plants. With those color temperatures, most of the emissions will be beyond the range of what is useful to aquatic plants. 

Also, in my opinion, they give an extremely stark look to the tank and inhabitants. I got a fixture which came with one 6700K and one 10,000 K lamp, and I used it for a couple of weeks. But... when the replacement lamp I bought arrived (a 5500K) to pair with the 6700K, I was far more pleased with the look of the tank. 

Also, all 5000K lamps are not the same. That's just the rated color temp, which is different than the actual wavelengths the phosphors are emitting. One may have strong output in the part of the spectrum we see as yellow and green, and another may have stronger output in the red and blue areas, or very even output across a range of outputs. 

-Jane


----------



## OverStocked (May 26, 2007)

10000k bulbs work great for plants. Perceived color temp has little to do with plants. This is what the human eye sees, and to be honest, most bulbs have a made up color temp. I can show you 3 6500 bulbs side by side and 1 looks like 3000k and 1 looks like 9000k... 

I have even grown plants fine with 14000k bubls, not that I really think they are actually 14,000k....


----------



## Riiz (Apr 30, 2008)

Even those 18,000K bulbs Hagen sells look nice and grow plants, so dont take those K ratings to seriously.


----------



## Hoppy (Dec 24, 2005)

I look forward to seeing some really "powerful" 27000K bulbs before long. Of course no one will be able to tell that they are different from 6500K bulbs by looking at the light they emit, but just imagine how "powerful" they will be.:biggrin:


----------



## xmas_one (Feb 5, 2010)

The Baron said:


> I kinda figured that.
> 
> I; trying to bring out the blues more in my rams and this bulb is not
> helping.
> ...


You can "google" the bulb model number and manufacturer, many times this can yield lumen ratings etc. 10000K or 6500K I'm sure either would be fine for your setup...


----------



## The Baron (Jul 9, 2010)

THank you all!


----------

