DIY CO2 Generator Bottle Caps - 2 Pack

These quick-twist CO2 generator caps are ideal for DIY aquarium setups. Designed to fit standard soda or water bottles, they allow you to create a CO2 reactor for your planted tank or even a brine shrimp hatchery.

One side connects to your air pump, the other directs gas or shrimp into your aquarium. Compatible with 4 mm inner and 6 mm outer diameter tubing, these caps make it easy to add or regulate CO2 for healthier aquatic plants.

Key Features and Important Notes:

• What’s Included:
  – 2 x DIY CO2 Bottle Caps
  ⚠️ Airline tubing and pump not included.
• Material:
  Durable plastic suitable for aquarium use.
• Size:
  Fits standard PET soda/water bottles (approx. 28 mm neck diameter)
• Compatibility:
  Designed for 4 mm inner / 6 mm outer diameter tubing.
• Multi‑Purpose Use:
  Perfect for DIY CO2 injection or brine shrimp hatcheries.
• Installation:
  Quick‑twist design for easy setup on common bottles.
• Warranty:
  1‑Year Warranty (T&Cs apply).