INFOGRAPHICS

Bottle 1: The Main 2L Yeast Bottle
For a standard 2-liter carbonated soda bottle, you must leave a massive headroom gap at the top so the foam has physical space to rise and collapse before it ever reaches your cap. Exact Ingredients & Volume:

-Dechlorinated Lukewarm Water (30C): Exactly 1.4 Liters (Fill the bottle roughly 70% full, do not exceed the curve where the bottle begins to narrow toward the neck).

-White Granulated Sugar: Exactly 2 cups (roughly 400 grams).

-Baking Soda (Sodium Bicarbonate): Exactly 1/2 teaspoon. (This acts as a pH buffer to keep the liquid from becoming too acidic, which stabilizes the yeast and prevents explosive, violent foaming spikes).

-Active Dry Bread Yeast: Exactly 1/4 teaspoon. (Do not add more yeast to try to get more bubbles; adding too much yeast causes rapid, uncontrollable foaming that burns out in a few days).

Assembly Instructions:
-Pour the 2 cups of sugar and 1/2 teaspoon of baking soda into the empty, clean 2L bottle.

-Add your 1.4 liters of lukewarm water. Shake vigorously until the sugar is completely dissolved and the water is clear.

-In a separate small cup with 2 tablespoons of warm water, sprinkle the 1/4 teaspoon of yeast. Let it sit undisturbed for 5 minutes until it activates and looks slightly creamy.

-Pour the activated yeast mixture into the 2L bottle. Give it one gentle swirl (do not shake violently).

Bottle 2: The Separator / Bubble Counter Bottle
Take a smaller plastic bottle (like a 500ml water or soda bottle) and equip it with a dual-port cap.

Exact Volume: Plain Dechlorinated Water: Fill it exactly 1/2 full (around 250ml) with normal room- temperature tank or tap water. No sugar, no yeast.