White Light

[Alexp08]

I have a tank that i just put two t8 bulbs on. I went from a crappy walmart LED light system. Well anyways the bulbs provide like a green light. Its called a "daylight" bulb, Lowes had it marked as a 6500k bulb. Well my question is, what K would provide a more white light. Similar to led lights. 
Thanks!

 

[attibones]

That should yield you a white light. Do the bulbs themselves look tinted at all? That Kelvin rating is suited for plants, so it shouldn't necessarily be green. However, my planted tanks do take a green sort of tint to them, not because of the lights but because of the amount of plants. I think (but I don't know for sure) that it has something to do with the green color of the plants reflecting into the water. So, I suppose, the best thing to ask is if you've got live plants in the tank?

 

[Alexp08]

I do have live plants yes. But i have live plants in other tanks and it doesnt give off a green tint

 

[fluttermoth]

It could be that your other tank's lights have a pinkish hue, that's making your white light look greenish in comparison.

 

[TwoTankAmin]

Here is the K info for Compact Fluorescent Lamps from AH Supply.

 
21,000K Bright Blue: All output in the wavelengths between 380nm and 500nm, with the peak output around 420nm. Sometimes combined with 6700K for a bright look that is still definitely blue.
10,000K Ice White: A strong white light with a slightly bluish tinge. Relatively low output of long, red wavelengths. Most commonly used over marine aquariums.
6700K Afternoon Daylight: An intense, very bright light like daylight in the middle of the afternoon under a clear, blue sky. Excellent for plant growth.
6500K Afternoon Daylight: An intense, very bright light like daylight in the middle of the afternoon under a clear, blue sky. Excellent for plant growth.
5500K Morning Daylight: A softer, warmer light like daylight around sunrise or sunset. Excellent for plant growth.
3-6-10 Enhanced Daylight: A daylight lamp that enhances the red and blue colors of your fish and makes red plants a richer, more saturated red, while adding a slightly bluish tint to the water. Excellent for plant
growth, as are the 5500K and 6700K lamps. The light from this lamp does not correlate well with any Kelvin (K) temperature. We call it 3-6-10 to suggest a combination of the red from 2700-3000K, the white from 6700K, and the bluish tint of 10000K.

from http/ahsupply.com/

 

[Byron]

This comment (on the "green" hue) is one that has been tossed at me several times on forums after I suggest lighting in the 6000K to 7000K range.  I can understand it, as when I sit and think about the hue, some of my tanks do seem similar.  And it will be even more obvious if you have been used to other light hues, as one member mentioned.
 
Assuming you have T8 fluorescent lighting, and two tubes, my advice is to get one 6500K and one 5000K tube.  Phillips and Sylvannia make these, so Lowe's (like Home Depot here) probably carry one of these manufacturers and you can get both tubes.  This adds a bit of warmth (red) to the mix.
 
Studies have proven that aquarium plants respond best to light in this range, 5000K to 7000K, peaking around 6000K.  This light is high in the red, blue and green wavelengths, and this drives photosynthesis better.  The green aspect is interesting.  Aquatic plants require high red and blue wavelength to drive photosynthesis, with minimal green.  Diana Walstad surmises that the improved response of plants to the mix containing green may be more to do with it being a brighter (more intense) light.  After all, it is the closest to natural sunlight at mid-day, so this would make sense.
 
Here's a photo of my 70g with the mix of 5000K and 6500K tubes.
 
Byron.