Dude, agreed they may get tall! Have you lollypopped them yet? Lollypopping is basically cutting everything on 1/3 of the bottom of the plant as you wont get much useable bud at the bottom branches, some people advise to leave the fan leaves though. This will increase the yield at the top of the plant as the plant does waste energy on popcorn buds that aint worth it.
If you dont lollypop, maybe some cfl sidelights to get to the bottom of the plants? 1 x 600watt will cover the canopy but your gonna get a lot of lower buds not getting light..Next time to max yield, def look into LST from the get go, your branches are prob to thick to now to mess with now. Have you topped them?