Capacitor help?

wup yall. my system consists of: Two 12inch L7's(powered by a Power Acoustik ad300bd mono, which is 3000 watts max 2300 rms), two 6.5's(no amp), two 6by9's(no amp) and a jensen flip out radio. now, after dealing with dimming for months i finally decided to get a capacitor to help with that. i purchased a three farad and the dimming lessened but was still apparent. so then i told myself, well maybe i need to upgrade my battery. i went ahead and put in a yellow top optimum battery and still the dimming is happening. my friend told me that 1 farad can cope with 1000watts of max power, so if i add up 3000(amp) and the subs(3000) should i get a higher rated cap?...