2700K vs. 6500K temp for macro

I'm upgrading my macro-algae's light today. I just want a little more power .Going from a 23W to a 26W CFL. My options at Target just now were 2700K or 6500K.

Which do you all think will work better?

 

Well 6500 is a lot whiter than 2700. Considering the suns light is whiter than it is yellow. I would go with the 6500k

 

But its in the refugium. So yellow is no problem if it will be more desireable for photosynthesis.

 

Ya, I always thought if you were trying to grow algae you wanted a warmer (i.e. red/yellow) light as opposed to blue/white. Typically when you see people's algae scrubbers, they're using incandescent lights which would be more similar to the 2700k than the 6500k

 

well, i dont know if it helps, but over my fuge, i have a 100WCFL at 5000k, a 100WCFL at 3500k, and a 10W coralife "colormax" self ballasted standard screwin base bulb... and my calurpa is starting to take off...

 

I've heard that a spectrum of about 2500K to 3000k is plenty for macro. I have two 20 watt halogens on my cheato and I have to cut it back all the time.

 

I'd go with 6500k as well. It is an extremely soft white light. should keep the Macro happy.

 

I use 6500K over my fuge.

 

I've had several different types of planted freshwater tanks over the years and 6500k bulbs are generally considered the better grow bulbs for plants. Assuming the same would hold true for macro algae.