When To Prune Lower Branches?

Can anyone tell me when the best time to prune off the lower branches in order to get a better all round grow? should I have done this during veg or can I do this during flower? My current grow is 9 days into flower.
Any help appreciated as always..

...exactly what i am wondering. what did you hear? how many tops should each girl have?

after about a month of flower, i have about 10 to 12 tips on each (cuts made from taking more
clones). is that a good bushiness for under a 600 in an aero setup, people?

i am thinking of putting a screen around the light so that i can route the tips with it to spread
them out and use more of the light...

Don't cut any branches unless they're 50% or more necrotic/diseased. If big fan leaves are blocking light to budsites, then they can be removed too. Just don't get too zealous because hacking your plant causes stress. Generally it's best to let leaves fall off on their own.