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tank18
04-12-2008, 11:54 PM
i just harvested a few days ago,with shity results. i have a 65 watt cfl,2 42 watt cfls,and 1 circle 30 watt cfl all crammed in a 1.5deep,1.5wide,3 foot tall homemade grow box.i grew 2 plants and am probably only going to get maybe a half ounce all together.i thought that would be plenty of light in that amount of space,i vegged for 2 weeks and flowered for about65 days.someone help me please im doing everything right but its so wrong.

Ausguy
04-13-2008, 02:11 AM
Well, here's the math:
Your area is 1.5ft by 1.5ft which is 18" x 18" (I use metric cm / m in Aus :hippy:)
Therefore: There is 144 square inches in a square foot.
18" x 18" = 324 sq. in.
324/144 = 2.25 sq. ft.

You have a space of 2.25 sq. ft.



2000 lumens sq. ft./21500 lumens sq. m. = Absolute minimum for growth. You won't get much from this, especially after the plant has grown a bit. Not really enough to flower well.

3000 lumens sq. ft./32250 lumens sq. m. = Pretty Good growth. Enough light for the entire light cycle, although your yields may be lower.
4000 lumens sq. ft./43000 lumens sq. m. = Very good growth. Once you pass around 3500, growth rate and ability goes up fast.

Over 5000 lumens sq. ft./53750 lumens sq. m. = Optimal growth. Dense growth in all stages.


So you want (for best results) 10,000 lumens give or take.



23w CFL = 1600 lumens = 69.6 lumens/watt
30w CFL = 2000 lumens = 66.7 lumens/watt
40w CFL = 2600 lumens = 66.3 lumens/watt


Look on the packet of which you bought the CFL's and see what LUMEN they provide and what KELVIN they are.

Watt's is just how much electricity the bulb uses, has nothing to do with growing.

Hope that helped :) :hippy:


P.S Vegging for 2 weeks instant a long time for the plants to build. You wont get a huge yield even at optimal performance.

tank18
04-13-2008, 05:22 PM
hey thanks,your info really helped me out alot,but i have added up my lumens and i have 11,100 lumens so that should be ok for thats box and just 2 plants,but like you said i only vegged for 2 weeks because i hag to worry about height and all that shit,when they were finished they wasnt even 2 foot tall so maybe thats the prob..ill have to try them lights in my small closet with 2 or three plants so i can let em get bigger and hope like hell for a better yeild.so thanks alot for your input man it helped me out alot.