iOS8 Photo Question

Hello,

I've updated to the new Icloud and moved all the photos from my camera roll to the cloud folder. The "camera roll" as it was once known is now empty. When I check usage, Storage, Photos and camera it shows:

My Photo Stream: .3kg
Shared Photo Stream: 2.9GB

How do i get those photos to only available on iCloud and not saved on my device? I was hoping to clear up that 2.9GB. It'll be a moot point once my 6 arrives, but We take a lot of pictures and videos and loved the idea of storing virtually rather than on the device itself.

Thanks all!