if the light wattage is significantly high then there is no need, Co2 sytems are generally for weaker, dimmer lights
(just had to tell evry1 how lucky i am, I Get 40% discount at my LFS cuz i help out every fridayThanks for that Tizer. I will be renewing both the tubes shortly so that should help the plants out tooyou wont really need it mate, to be honest.
I have got a 20w Power Glo and a 20w Aqua Glow lighting Tizer