Light intensity is key in getting dense buds.
Also the type of lighting helps as well.
LED vs CFL vs HID
you want at min 100W from a grow light in led.
watts X 1.66 to find LED to CFL equivalent
watts X 0.66 to find CFL to LED equivalent
you need about 166w in CFL lighting to have a descent grow.
your diary says your using 39W if there's two bulbs in that ballast, that's now 78W
you want to double your current setup.
I use Sunblasters LED lineup.
Normal 6400k mixed with their craft cannabis 3000k 50/50 mix
Outputting a total of 300W currently.
this was my grow off of 126W led only in 6400K start to finish, it did pretty well.
.9w/g ratio of total combined bud + trim for edibles off of two plants.
GD only does g/w ratio off of one plants bud yield and total light output. does not make sense to me.
growdiaries.com/diaries/49742-dinafem-og-kush-autoflowering-grow-journal-by-m0use
Best Of Luck and Happy Growing.