Light question
 

I have a grow light for starting seeds with a high output 4' T5 6500K 54W light bulb (not sure of lumens off hand). I have an extra 4' shop light with slots for two bulbs, so I thought I'd rig it up for some extra lights on my seedlings (never a bad idea to have more light, right?)

I bought two daylight 6500K 4' T12 bulbs (at least that is what the cardboard sleeve said): (e.g. [url]http://www.amazon.com/Sylvania-24477-Straight-Fluorescent-Light/dp/B000BO5A1Y[/url])
[LIST][*]Color/Finish: Daylight[*]Color Temperature: 6,500K[*]Average Lifetime: 20000 hours[*]Lumens (light output): 2180[*]CRI: 88[/LIST]But when I took them out of the cardboard sleeve, one of them was actually a 3400K 4' T12 aquarium/terraium/grow bulb (e.g. [url]http://www.amazon.com/Sylvania-24671-Fluorescent-Aquarium-Terrarium/dp/B000M2TX22[/url])
[LIST][*]Color Temperature: 3,400K[*]Average Lifetime: 20000 hours[*]Lumens (light output): 1700[*]CRI: 89[/LIST]At first I wasn't pleased, but then I thought the mix of 6500K light and 3400K light might not be a bad thing. Any thoughts on these two bulbs for seedlings? Compared to just two 6500K bulbs?

The lower 3400K is more for flowering (red).
I have heard of people mixing them I have no idea how it would turn out.

So you said you had a total of 3 6500 (blue) and one 3400 right for a total of 4 lights?
If so they should be good.

Worth

No, one fixture is a single T5 bulb 6500K (a 4' purchased grow light before I knew shop lights would be just fine), it is notably brighter than the 6500K T12 bulb--so I'm guessing the lumens is a fair amount higher.

So at present I have 2 6500K and 1 3400K. My single T5 bulb has worked fine in the past, but I'm going to have a few more plants this year so I thought adding some more light wasn't going to hurt.

Funny, I was faced with the same thing because I had a 2 bulb fixture...and some extra 3400k bulbs. As W said...the lower k bulbs are good for "full spectrum" light for continuous growing/flowering. My research told me to dump the 3400k bulb and go with two 6500 bulbs. It is working out great!:yes:

The last bulbs I bought are 4100K and work great. I don't think seedlings are that picky about spectrum.

I probably won't hassle with taking the bulb back to the store then. I've learned to check what bulb is in the box despite what box it is. I'm glad I've got the extra light, which is allowing me to start a few more tomatoes, peppers, and flowers.