Glass CO2 Beetle Counter

A unique glass bubble counter designed with an internal spiral. Easily count and adjust the number of CO2 bubbles rising in the spiral to regulate the amount of CO2 entering your aquarium.

• Handcrafted glass bubble counter.
• Use to count CO2 bubbles entering the aquarium.
• Quick and easy to count the bubbles as they move through the internal spiral.
• suction cups included for mounting
• recommended for use with a check valve