A little more info would help:

1) What is the wattage of your CFL's?

2) What is the wattage and color temp. of your T8's? How long are they in inches/ft.?

3) How far are the CFL's and T8's positioned from your mature plants or seedlings?

4) How large is your grow area? Example: 3x5-feet

5) Will you be growing 100% indoors? Is any direct sunlight available?

Hey chefrobert!

Thanks for the Q's, ya I guess that would help.

1) Wattage of the 4 CFLs are 32W each.

2) Color temp is 4100K and they are 4 feet long a piece.

3) Seedlings aren't quite up yet but when they do pop, the lights will be a mere inch away from them.

4) My grow area is 5'x 3', so not too big, but adequate for my setup.

5) No, the plants will eventually be transplanted into my raised bed garden I built this year!!!

Thanks!!!

I'm confused.

"I bought 2 cfl fixtures" "Wattage of the 4 CFLs are 32W each"

"I put 4 GE T8 bulbs in them" "they are 4 feet long a piece"

...Two CFL bulbs are not compatable with a dual 4 ft. T8 fixture.

How many CFL bulbs and fixtures do you have?

How many 4-ft. T8 bulbs do you have? Is it a dual bulb fixture?

What is the total wattage of your T8 fixture? Example: Two 54-watt bulbs would equate to 108 wattage handling for the dual fixture.

32-watt CFL's emit roughly 2100 lumens each.

I don't know what your confused about.

I have 2 fixtures that hold 2 bulbs each... thats 4 bulbs

So I have 4 T8 bulbs in the fixtures.

T8 bulbs mean that the bulb is 8/8ths of an inch or 1 inch across...a T8 bulb is the same as a CFL bulb... it just describes the size.

EACH bulb is 32W a piece.

EACH bulb has a color temp of 4100K

EACH bulb is 4 feet long....

I guess I don't know why you're confused. I thought I put it pretty bluntly.

I think hfg is confused. T8s are not CFLs.

Here are some pics to clear up some confusion.

@hfg

This is a CFL bulb: http://brightestwitch.files.wordpress.com/2007/04/cfl.jpg

These are CFL fixtures:

http://www.expresslightbulbs.com/bmz_cache/2/213880deabace56a15d3df47cdfc9fb1.image.121x100.jpg

http://www.sunflowersupplies.com/product_images/z/hydrofarm_110v_cfl_cordset2__64866.jpg

This is a T8 fluorescent fixture:
http://www.lightworld.com/images/md/t56-lamp.jpg

This is a T8 fluorescent bulb: http://www.sunshinehydro.com/images/fluorescent%20tube.jpg

Ah... I got it. Ya just a little confusion... Technically a T8 IS a cfl, but a CFL is not a T8... thanks for clearing that up though!!! Appreciate it... others will definately benefit from that.

Great! Those are T8 Fluorescents. No CFL's (Compact Fluorescents) are being used here. Your lumen count is adequate for growing seedlings. Everything is fine. Any more questions?

"Technically a T8 is a cfl"...

How do you figure?

http://en.wikipedia.org/wiki/Compact_fluorescent_lamp

Nope not really, do think it's necessary to have a small fan to harden the stems and firm the seedlings up a bit?

A fan would not be needed until the seedlings are about 4 inches tall. At the seedling stage, a small fan will help prevent damping off and might encourage hardier seedlings.

As the plant matures (if you were to grow them 100% indoors) then a fan should be run 24/7 to promote circulation and a strong plant.

'how do you figure'

Non-integrated CFLs

There are two types of tubes: a bi-pin tube designed for a conventional ballast, and a quad-pin tube designed for an electronic ballast or a conventional ballast with an external starter.

A bi-pin tube contains an integrated starter which obviates the need for external heating pins but causes incompatibility with electronic ballasts.

There are different standard shapes of tubes: single-turn double helix, double-turn, triple-turn, quad-turn, circular, and butterfly.

Since the ballast for a non-integrated lamp is part of the light fixture, it can be larger and more durable than one integrated with a lamp, and it does not need to be replaced when the bulb reaches the end of its life.

99.9% of the T8's that are used for growing seedlings are 2' or 4' linear bulbs with two pins, none of which are ever referred to as CFL's by growers.

Look here for better clarification:

Linear (non-CFL's): http://genet.gelighting.com/LightProducts/Dispatcher?REQUEST=CATEGORYPAGE&PRODUCTLINE=Lamps_Linear%20Fluorescent&CHANNEL=Commercial

CFL's:
http://genet.gelighting.com/LightProducts/Dispatcher?REQUEST=CATEGORYPAGE&PRODUCTLINE=Lamps_Compact%20Fluorescent&CHANNEL=Commercial

I see where the confusion is...

You were comparing to plug-in CFL's vs. self-ballasted CFL's. They have nothing to do with Linear T8 Fluorescents, therefore T8's are not CFL's.

4' might be compact when talking cars, but not lights.

A fan is beneficial no matter the size of the plants.

You newbies can continue to argue but I'm gone. You both need to read MUCH more than you post.

tee, he, he!

Mike

@taz: Who is arguing? May I ask why you are labeling me and what advice was incorrect in your "humble" opinion? I think that I provided sound advice whereas you have simply stated insults.

Try blowing a fan directly at 1-inch tall seedlings with no leaves in a small amount of soil and see what happens. The soil will dry out very quickly and the seedlings will bend. That is not to say that air circulation should not be provided.

I agree Rob... what the heck. He gets off on thinking he is better than everyone... I'm glad you and I can have a civil discussion without disrespecting other people. Thanks again.

Yes, I've noticed catty remarks by taz in other threads. He even began rudely in this discussion. I just ignore the attitude of those who "think" they know it all without providing a valid reason. Keep in mind that I'm new here, but I'm not new to gardening.

hfg, a fan is not needed for seedlings but if it makes you happy then you can use it. Just don't blow it directly on the delicate seedlings. I've grown hundreds of strong, healthy plants without any issue of damping off or weak seedlings by implementing a fan after I transplanted them into 3-inch pots. Though, I use HO-T5's and HPS lights. As long as you take the humidity dome off a few times a day, you shouldn't have a problem with damping off.

To each their own - there is no "best" way to grow plants. "Most" growers recommend using a fan for at least 30 minutes a day and not just after seedlings are transplanted. Again, "most" growers remove the humidity dome when the first seed germinates and breaks through the media.

If I had my druthers, I would germinate seeds in a room where the temps were 85 degrees and once transplanted, put them in a room with a huge overhead fan but where them temps stayed at 55 degrees. They would get 2,000 FC of light and be bottom watered with rainwater mixed with Tomato-tone fertilizer, with some multi-purpose vitamins mixed in.

YMMV,

Mike

I am UNLIKE most growers, as you say, if most run their fan 30 minutes a day regardless if the plant is 1-inch tall or 4-ft. tall.

I am LIKE most growers, obviously, in that I remove the humidity dome when the first seed germinates and breaks through the media.

Why such a low temperature after they are germinated? Is cold-hardening recommended for plants kept 100% indoors throughout their life cycle?... Or is this method more suitable for plants that are later transplanted outdoors?

Is newbie an insult? Lighten up! You guys are waaaaaaaay too serious.
A fan on low should not hurt sprouts. If it does they already have damping off.

Lower temps with bright lights promote short, stocky plants. Higher temps with lower lights induce legginess. Bottom watering encourages root growth.

Mike

Mike,

I'm pretty sure that depends on the plant. I doubt that all plants, particularly those accustomed to the Tropics, enjoy a constant 55 degrees F throughout their lifespan. I know it's a different story when you're growing indoors, but I've seen excellent results the way I'm doing it. I'll stick with 60-70 night / 75-85 day temps. with bright lights for my plants. Though, I'm not against a defined, cold-treatment period for certain plants.

Oh, no way do my seedlings stay that cool. It has been in the mid 80s recently in the grow room and in the GH in the mid 90s. And they would need higher temps to set fruit, at least the toms and peppers. But for short, stocky plants lower temps help tremendously.

Mike

Be careful though, if temps and humidity are too high, it will actually hinder fruit set. The pollen gets stuck when the weather is hot, sticky and moist. I'm pretty content with my temp. guidelines. I don't think it's necessary to go above 85 F for tomatoes and peppers. Best of luck.

Thankfully, the humidity is low and the fan runs 24/7. It should cool back down for a few days - it's only suppose to be in the upper 50s this weekend.

Mike

I don't like it very much. I really think your color temp is too warm. Take those bulbs back for best results try to break above the 5k mark.

The CRI would improve over 5000k also.