Heat 20 centilitres of water without boiling it and infuse the tea, adapting the infusion time to the tea used. Then take the tea out, let it cool down and put it in a cool place.
Bring water to a boil in a saucepan. When it boils, turn down to medium heat and pour in the tapioca pearls. Cook according to package directions, in my case 15 minutes.
While they are cooking, do not stir them very much and very gently because they are fragile.Drain them and pour them into a bowl. Add the syrup or the fruit juice of your choice. Divide them into 4 tall glasses and pour the cold tea over them.Add ice cubes and water to the top of the glasses. Serve with large straws and enjoy cold.