my grow box, please give tips

Hello folks I built myself a growbox around 1 meter squared, 1 and a half meters high, painted the inner walls flat white, and used 4 150W cf builbs, growing northern lights in john innus NO3 soil+perlite, using miracle grow

Ive had 2 successful harvests with a good stone, with both i veg around 4/5 weeks on 18-20 hour light, then 2 months flower on 12 hours

both times i had 1 plant turn oot male but i removed that early on.

here are some queries.
after smoking bud, it felt a waste throwing leaf and branches away, is there any thing i could do wi them??

i did not use any fan but opend the box each day, would i benefit from a fan in any way?

please tell me if theres anything i shuld be doing for better results???

cheers

?? anybody oot there

a fan will help with circulation, in my exp and what i read the more fresh air you give your plants the better. if heat isnt an issue then just a small oscillating fan should do the trick. also if you get the fan to blow accross the tops of the plants between the plant and the lights youll be able to get the light a little closer. this should help your light penetrate better to the lower branches since cfl's dont penitrate to far. other then that looks like youve have a few nice grows.