"READ THE INSTRUCTIONS ON THE LABEL": This is advice that is offered numerous times throughout poolmanual.com. We at poolmanual.com, along with your chosen local pool professionals, will advise you HOW to achieve proper water chemistry. But, the various manufacturers of chemicals may offer slight variations of "X" LBS per 10,000 gallons of water and slight variations on how to add the chemical to the pool (either diluted first in a bucket of water or poured in straight from the packaging). Therefore, always "read the instructions on the label before adding any chemical." Even when you get in a routine and become the expert pool operator that you will soon be, get in the habit of "reading the instructions on the label," especially if you alternate or altogether change brands. NOTE: Did you count how many times "read the instructions on the label" was mentioned in this last paragraph? It is very important.