When adding large quantities of granular cyanuric acid (chlorine stabilizer), such as right after completely refilling filling the pool with tap water, take the lid off the container, keep the container upright, slowly lower the container into the pool (minimizing the amount of granules that escape the container), and use a hook with a long handle (like a hoe) to ease the container by its handle all the way to the bottom of the pool at a flat spot such as in the shallow end. Allow the container to sit with the granules inside until the crystals are all dissolved (which may take 2-7 days). Do not run the Polaris -- it can topple the container, putting granules in direct contact with the vinyl and damaging it.
This process prevents the granules from accumulating in the filter (resulting in sky-high pump pressures) or in the IntelliChlor (where they may damage the blades). It presumes no one will be swimming in the pool until the granules are completely dissolved.
Better yet, spend the extra money to get the instant liquid salt-based chlorine stabilizer instead.