Quote Originally Posted by ksturge
Does shock do something more than the bleach does?
Yes, it costs you more . All you really need is Liquid Chlorine, AKA: Bleach. To shock your pool just use more. To chlorinate your pool, use less. Dosage for shock or chlorinating can be found here:

http://www.poolforum.com/pf2/showthread.php?t=365