more bulbs more lumens....... more heat?? just keep air circulating and they will be fine just keep the cfls on for right now until you get a desired height (all basically depends on strain so do a lil study on your babies such as sativa/ indica ratio) after that never ever let any light hit them during flowering a hps will be good for that because it has the red spectrum that it likes... your plants depend on you to play mother earth which you already know so nutrients are a big deal when it comes to quality... hope this helps