Pineapple - I've got a JL system. Last system I was running a 450/4 & ONE 1000/1. I tried a 5 farad cap & my lights & voltage still dimmed badly. I upgraded to a 15 farad Alumapro cap (about $400 new/$180 used) & I STILL had the same problems.
My new system consists of the same 450/4 & now TWO 1000/1s. An authorized Batcap dealer on
eBay (ricktw) HIGHLY recommended ONE Batcap 800 per JL 1000/1. I found a sweet deal on 3 Batcap 800s. With 2450 watts (2000 of it for bass), the Batcap 800s work beautifully.
FYI - A Batcap 800 is about $175 new & is well worth it. A Batcap 800 is described as 70% battery & 30% capacitor. One should be all you need. Hook the Batcap 800 right before your 500/1's fuse. Search the want ads on this forum & carsound.com. Every now & then, you can find one that a sound competitor used for a show or two...usually for about $100-$140 plus shipping.