Shocks are an essential problem solver as well as great preventative medicine for your pool. The poolife brand offers a range of shock products to meet your every need and help maintain water by killing bacteria, controlling algae and destroying organic contaminants. These shock products comply with EPA dosage recommendations for shock products (i.e. deliver between 5-10 ppm of available chlorine per recommended dosage).Poolife calcium hypochlorite based shock products will NOT cause overstabilization - even with prolonged use.