How much CFL total wattage...

[w3weasel]

I'm zeroing in on plans for my grow cabinet.

The cabinet will be 36" x 24" grow area.

I will be using standard Compact Fluorescent exclusively. I'm trying to work out the light arrangement and I want this installation to be safe and well thought out. I'm probably going to wire it up with proper electrical work boxes and standard electrical sockets installed in them so I can use the plug-in type light socket.

So to move my planning along, I an wondering just how many lights I should be trying to get in there.

I will be using 23 watt CFL's.


Now... I know that the answer to my question is "You want as many lights as you can fit". But lets be realistic. I want to handle the cooling with between two to four 120 mm PC fans.

My initial thought is 10 bulbs for a nice round 230 watts.

Should I aim higher?

Is this way to little light for 6 square feet of grow area?

is 20 bulbs insane?

Lookin for some input from a CFL mentor!

 

[HeD333]

I used 5 inside a rubbermade. It worked well. Scale from there?

 

[w3weasel]

do you remember what gallon size the tubs were?

 

[2Lazy]

I'm using 6 bulbs (about 150w total) in a cabinet of those dimensions with good results. I'm growing 5 clones straight to flower. They range from 6" to 10" and one of them is a little too laden with buds and lays down sideways.

Here's a really weird angle of a Kandy Kush x Skunk clones I have in there. They are way more frosty than the Kandy Kush mother I have flowering under a 400w HPS. I think it's the wavelengths but I can't be certain. Does seem like I'm getting much better trichome production on these smaller clones under mostly daylight CFLs.

I had a bitch of a time trying to rig my lighting. I sorta half assed it too... Definitely could have done a better job. I'll take a full on picture tomorrow to give you an idea of my results with this particular strain in coco and how I have it set up.

 

[monoclepop]

I previously used a bunch of 20W 2100k spiral cfls - had 6 of them in a tiny cab. With two low cfm 120mm fans it got fairly toasty ime. Also light intensity was poor.

Last week I swapped in 4 new 45W U shaped bulbs on the 6400 spectrum. Plants responded immediately with buds swelling dramatically. The cab is actually cooler than before despite doubling in light intensity. I've decided that spiral bulbs are more trouble than they're worth - only a small fraction of the bulb is exposed to the plants. Spirals are harder to cool too, to go along with the smaller light-emitting surface.
Not to mention that the 20w lights don't seem any cooler than the bigger lamps.

So I wouldn't use 20w bulbs again where it counts - for cloning yeah, whatever. I'd go pll if I could source them, but as I can't these higher watt U shaped lamps a way better deal than what I had originally.

All in my experience and opinion, but in your shoes i'd try to use much higher watt lamps, even if you are on a budget.

 

[darwinsbulldog]

i use 4 in a space about half that size, so you can probs get away with 8, but in the end just put as many as are needed and as many so that the temp isn't above what is best (78F/30C i think?). in the end it's not so much how many, but how much light is going to be getting to the plants, if they're several feet away from the lights you'll need more than if they were only several inches away to get the same growth rate etc.

 

[tube dude]

As a rule of thumb for flower you need a minimum of 50 watts psf. You only need about half that much for veg. Personally, I run 76 watts psf and mix the spectrums. It seems to make the buds alot tighter.

 

[ukganjafarmer]

yes 20 x 23w cfls is insane lol

have u looked into pll's?

 

[thaiboxer]

i recently bought a pack of 4 - 60 watt equivalent - 14 actual wattage 900 lumen 2700k bulbs for less than $5 figuring the smaller wattage would be cooler & will target 10 k lumen in for a micro grow. maybe 5-6 of the small ones & a couple daylight spectrum to fill in the 10K.

More info from any optimization watts/lumen/heat experience would be awesome.