6500K v.10,000K lights

[Scott F]

I have an Odyssea light set up ( 4 bulb ) that came with 2 10,000K lights. Would replacing them with 2 6500K lights be better for growing plants, along with a couple of floramax style bulbs ??

It sits on top a 55 gal but I'm only running two lights at the moment ( a 10,000K and a plant bulb).

 

[Viper]

I actually just bought a Current USA SunPaq 6700K/10000K Dual Daylight bulb. I figured it would give me the best of both worlds in terms of visual appearance and my plants would enjoy it as well.

I will be using it in an Odyssea fixture as well. The bulb is a bit on the expensive side though

 

[BBradbury]

55 G Lighting

I have an Odyssea light set up ( 4 bulb ) that came with 2 10,000K lights. Would replacing them with 2 6500K lights be better for growing plants, along with a couple of floramax style bulbs ??

It sits on top a 55 gal but I'm only running two lights at the moment ( a 10,000K and a plant bulb).

Hello Scott...

I can tell you the 6500K bulbs are recommended for planted tanks, because the light blue color hue comes closest to natural daylight at 5500K. I have a two light fixture with one 6500K and one 10,000K bulb in my 55 G tanks and the low light plants in the tanks do very well.

Try replacing just one of the 10,000K bulbs with a 6500K and see how that works.

B

 

[fort384]

I have had several planted tanks that used 10,000K exclusively, and I have never noticed any difference in growth or health from tanks that use 6500K or a mixture of 10,000K and 6,500K bulbs.

 

[BillD]

Actually, 5000K tubes are closer to natural sunshine than 6500K tubes, and grow plants very well. In fact, in my experience they are better than 6500K for plant growth. The reality is that plants need certain wavelengths of red and blue light, and if the tube provides them, they will grow. the colour temps are an approximation and a way to describe the look of the tube. CRI will tell you how well the tube renders colour. To render colour well, a tube needs to have most of the wavelengths covered.

 

[fort384]

All good points Bill. We get hung up on color temp, when really the important thing here is peaks in red and blue. IME, anything between about 5000K-12,000K will grow plants. I have seen evidence that plants will be fuller and less leggy if you stick to the low end of that range, but anecdotally I have tried em all, and really haven't seen anything definitive that 1 combo is better than another. So long as there is red and blue peaks, plants can use the light.

 

[Scott F]

Well I got a 6500K from a buddy at an electrical shop today so we'll see how it works. I'm just running two lights now,and doing PPS-pro calculator for ferts, because if I do all four I'd probably want to run a CO2 setup.

There seems to be such a wide consensus that I thought I'd try and narrow it down a bit.