hey bro I been thinking about you saying your co2 didnt seem be doing much, I can tell ya why it might not be doing very much. Normally you don't add co2 unless your at your light saturation approx 75-100wpsqft, you have 3x3=9sqft X 50wpsqft=450watts @ 75w=675w.. I think you said 180w? that's=20w per sqft, your very much under where ya want to be, minimum you want is around 50w per sqft,okay
also there more then just light saturation when using co2 you have run at much higher temps then if your not using co2. many factors when using co2, you need other things dialed in before wasting any cash on UN-needed co2