6700k vs. 10000k

[mrkho]

im currently using both of these light bulbs on my fixture, and i was told by my lfs that the 10k light gives out more algae because it has a little blue in it. would it be better if i switch out the 10k bulb and put another 6700k on it? any opions?

 

[flamingonhot]

It shouldn't matter.
From what I understand blue and purple penetrate water better and are beneficial for corals and other photsynthetic critters. The higher the number in Kelvin the more blue light it gives off.

You can stay with your current lighting unless you don't like the intensity of blue that 10000K light give off.

 

[MT79]

Not sure about the algae connection in FW, but a 10k will be alot easier on the eyes IMO. 6700k will be very yellow in comparison.

 

[flamingonhot]

oh... didnt even notice this was in fw lol.

 

[An t-iasg]

I agree with MT79's assessment of the appearance of each light, but it will also depend on the color of your substrate or whatever else it reflects off.

I got two identical light fixtures, for two tanks, and put a 6700K bulb in one and a 10000K bulb in the other. The wattages were identical. I just wanted to see which one I would like. IME, the 10000K gave me lots of algae - hair algae and diatoms too. The other tank with the 6700K light had very, very minimal algae. I ended up removing the 10000K light. I gave it to someone with a SW tank and I got another 6700K bulb for that fixture.

 

[travis simonson]

I prefer 10000K over 6700K for color, but it can cause colors to wash out a little bit IMHO. Of course I'm color-blind so don't pay attention to my analysis of the finer points of color wash out I use a mix of roughly 30% 6700K, 25% Actinic03, and 45% 10000K. I don't feel that the the high blue of actincs or 10000K leads to increased algae and I really like the way the three color spectrums mix. 10000K works just fine for growing plants.

 

[malkore]

Your LFS doesn't understand color temperatures (Kelvin temp).

10k is fine, 6700k is fine, 9325, 8800, 8000, even 5000 is fine, but it looks a little to yellow for most people's taste.