Pre-dissolve calcium hypochlorite granules before adding.

Yes, every time. Tossing them straight into the pool is how you get bleached liner spots, cloudy water, and undissolved sludge sitting on the bottom.

Fill a clean bucket with water—never add water to the granules, that can cause a chemical reaction. Slowly pour the granules into the bucket while stirring. Let it dissolve completely, then pour the solution around the pool’s edges while the pump is running. Do it at dusk so the sun doesn’t burn off the chlorine before it works.

One more thing: wear gloves. This stuff is strong enough to irritate your skin. Your pool will be clear and your liner won’t have white splotches.