Even with Cookie's help, there is a limit to the amount of potions Candice can collect and store.
But don’t worry, if you have collected too many of one type of Potion you will see that the Potion bottle is overflowing.
You can also keep track of your potions in Candice’s Workshop. Simply look for the number to the left, below the potion bottles on the shelves.
Any Potions you collect when your Potions are full will not be added to your inventory. If you run out of space use Candice’s magic to craft available spells. This will free up more space in the Workshop and assure that no Potions go to waste.