CO2 Starter Refill

Refill pack for the Dennerle Bio CO₂ system — an additional 60 days of CO₂ production for your planted aquarium.

✅ Tracked UK delivery  |  ✅ Carefully packed  |  ✅ Suitable for Caridina & Neocaridina tanks

The CO₂ Starter Refill is the official replenishment pack for the Dennerle Bio CO₂ system. It allows an additional 60 days of CO₂ production, providing a cost-effective way to continue supplementing the important nutrient that aquatic plants depend on for healthy, sustained growth.

Contents

• CO₂ Powder Mix
• CO₂ Activator × 5

Usage Tip

For best results, follow the detailed instructions included in the package. Refill the CO₂ Activator every 14 days, or when CO₂ production has dropped to 5 bubbles per minute, to maintain consistent output throughout the cycle.

Frequently Asked Questions

Is this refill compatible with the Dennerle CO₂ Starter Kit?
Yes. This is the official refill pack for the Dennerle Bio CO₂ system sold in our store. It uses the same bottle and diffuser from your original kit — simply refill and restart the fermentation process.

How long does each refill last?
Each refill provides up to 60 days of CO₂ production at optimal room temperature (20–25°C). Cooler temperatures will slow fermentation and may reduce the duration slightly.

When should I use the CO₂ Activator?
Add the CO₂ Activator every 14 days, or when CO₂ production drops to approximately 5 bubbles per minute. This restarts the fermentation process and restores CO₂ output to full capacity.

Is bio CO₂ safe for shrimp?
Yes, when used correctly. Maintain stable CO₂ levels and ensure adequate surface agitation. Avoid running CO₂ at night when plants are not photosynthesising. Suitable for tanks housing Neocaridina and Caridina shrimp.

How is this delivered?
All orders are dispatched from the UK with fully tracked delivery. The refill pack is carefully packed to ensure all components arrive in perfect condition.