I LOVE the Bum Genius! We also cloth-diaper, and they certainly don't hold as much as paper diapers. I have to change my cloth-diapered son every hour and a half while he's awake, whereas when he's wearing paper diapers, he can go more like 3 hours. Plus, such young babies pee like every 30 minutes, so those diapers are probably filling fast! I think it's just the nature of the beast. You can cloth diaper at night (I'll be honest - I don't. It's just a hassle, so I use my cloth by day and paper by night) by putting several pre-fold diapers in the diaper for absorbency, but it will make the baby bum very bulky. If you don't know how to fold a prefold diaper, do a Google search. Prefolds can be put in the pockets of the Bum Genius, as well as laid outside the pocket for extra. You may have to wait until your baby is a big bigger, though.
I don't know where Clayton, OH is, but if you're anywhere near Cincinnati, the Park + Vine has free cloth-diapering seminars on Sunday afternoons, or you can just drop in any time to get a one-on-one lesson about how to effectively use the diapers. I bought organic prefolds, Tinkle Traps, Motherease, and Fuzzi Bunz there as well as the Bum Genius. They're a great resource. Good luck!