If you don't already have a PH meter, you will need one. PPM meter is nice too but you need to keep up with PH daily.

Your plants look happy. That's good. I don't want to bust on CFL's they are good for veg time.

However the bigger the lights the bigger the buds. Have fun and see what works for you.

If you could see the dif in lights you would go straight to the 1000HPS for flowering and trichome production. If you like do a search for loc nar and you will see some of my grows. even the one they busted me with.