Background: (12) seedlings started braking ground 14 days ago under 2 - 4Ft/40Watt/6500K/2325L fluorescent fixtures (9300L total). Tomorrow the sockets arrive for my build out of CFL's and I plan on building two 4 ft light strips each with 4 bulb cluster bakelite style sockets; this will allow 16 23W CFL's (half 2700 & half 6500 is plan) or 25,600 per light 4ft strip. Both strips together will generate 51200 lumen for a grow closet approximately 11 sqft (floor) with a height of 6 ft. Should give me about 4500 lumen per sqft. The seedlings are doing fine and as normal they broke ground over a 3 1/2 day period meaning not all at the same time so they range from the largest (#1) that is 3.5" high with leaf spread of 5" to the smallest (#12) about 1.75" high with leaf spread of 2.75".

Questions:

(1) Should I only install one of the new CFL strips (25600L) at this time? Wait till I transplant from 18 oz soho cups to 3 gal containers in 10 days increasing spacing and plants being bigger to add the second CFL strip? Or go for using both putting 51200 lumen on the babies? Read you can't have too much light as long as the ventilation is right to keep heat below 80F. Which brings me to the second thought...

(2) Kind of wondering if those two old 4FT/40W tubers may be actually generating more heat than both CFL strips of 23W (32 total) bulbs will produce? The old fixtures are hold overs from the 1970's and they burn hot so I have a vent hold in the top of the closet to attic (using convection current of hot air rising) inside with a 16" fan blowing room air conditioned air under door (cut 3/4" off door bottom). Enough breeze that the plants dance 24/7. Temps during high heat of the day right now are around 84F to 86F. Evening temperatures are 78F-79F. Anyone seen any math formulas for calculating heat build up using CFL's per watt?

Note: my cost of parts to build each 4 ft strip generating the 25600 lumen is $40.15 each for all parts including CFL's and then my time which I figure it will take me about 30 minutes to wire each and then add the reflector. For the reflector I'm using mill finished aluminum flashing which I have spray painted with Rust-Oleum High Temperature Flat White. Power wire using 16/2 15 amp extension cord by cutting off 3 outlet female end and attached wires using Ideal Push In Connectors as they cost only $1.47 while brand lamp wire is 18/2 and cost $5.98 (GE) or $6.98 (Westinghouse). i.e. the 16/2 is is a step up in handling the amps than the 18/2 and $4 to $5 cheaper. Each 4 ft strip will draw 1.52 amps and the sockets come with 12" black/white pigtails soldered in. Then again, I could solder the connections and then shrink tube the connections closed.

Thank you and have a great week everyone.
FreddieFreeloader Reviewed by FreddieFreeloader on . Transitioning Lights In Grow Closet Background: (12) seedlings started braking ground 14 days ago under 2 - 4Ft/40Watt/6500K/2325L fluorescent fixtures (9300L total). Tomorrow the sockets arrive for my build out of CFL's and I plan on building two 4 ft light strips each with 4 bulb cluster bakelite style sockets; this will allow 16 23W CFL's (half 2700 & half 6500 is plan) or 25,600 per light 4ft strip. Both strips together will generate 51200 lumen for a grow closet approximately 11 sqft (floor) with a height of 6 ft. Should Rating: 5