design help for exhuast fan/lights

hello,

I have 3 6" vortex fans (rated around 435CFMi) my grow room is approx 420cfm. one will be for my cool tube. the other two for intake/exhuast. Can anyone suggest particular, low cost, dual outlet timer for my light/fan that I can set for 18/6 and 12/12 settings? And for my exhuast/intake should I find interval timers for, running at full speed for shorts times 24/7, and if so which ones? or just get a speed controller for each running them 24/7 at desired level?

No O2 as of yet will be used in this grow enviroment. but would like to upgrade eventually. So whatever I buy I want it to have some use if possible for when I do get O2 system.

I like interval timer idea for the intake/exhuast, due to the fact that the fans are rated at 130watts... however, will that cause them to wear faster, sense they are constantly being turned off and on at full speed? If you had the same exact thing what products would you get to make it run how you would want it? Keep in mind I like simple, and cost effective. What would you do?

There just seems several methods to do it. Tell me exactly what timers you would buy to do what you would do.

Thanks WP

you're better off getting the variable speed controllers and running the fans constantly at lower than their rated speeds. you can get better ventilzation and lower energy costs.