Good quality LS by the pound is far better than the bagged stuff. The bagged stuff only contains sand and bacteria, while the regular LS may also contain snails, pods, and other beneficial critters.
LS is better u get more critters but it is also more expensive, usually the bagged sand is good enough because when you add ur LR it seeds the bagged sand
i added bagged LS then bought a few pounds of LS from my LFS to help things out
