Drinking water can help you lose weight, whether you're restricting your calories or not. Consuming 2 cups of water before a meal helped a group of obese adults lose 2 pounds over a 12-week period without making any other changes to their usual intake, according to a 2015 clinical study published in Obesity.
How many tea bags should you use to make a half gallon of iced tea? One gallon is about 128 ounces, so if one tea bag is good for 10 oz  of water, then about 10 teabags is good for a gallon. Start with 10  and adjust accordingly with water.
Iced tea can also be brewed by placing tea bags (or loose tea) in a large glass container with water and leaving the container in the sun for a number of hours. This often results in a smoother flavor. An advantage is that sun tea does not require using electricity or burning fuel, thus saving energy.