A TikTok trend called 'stacked water' involves adding multiple ingredients like vitamin powders, fruit, honey, chia seeds, collagen, creatine, electrolytes and coconut water to regular drinking water to enhance hydration. The trend transforms a free glass of water into an expensive beverage costing nearly $19 with various supplements and additions. Two presenters demonstrate the concept by creating their own versions, with one making a humorous 'pizza water' using unconventional ingredients like Twisties, Tabasco sauce, honey, chia seeds and vodka.