- To be used with CO2 drop checker
- Solution changes color to provide quick and accurate indication of CO2 levels in an aquarium
- Adding aquarium water is not necessary
- Recommended to be changed once a month or when the color fades
- 10 ml bottle
Yellow: high CO2 (danger to fish)
Blue: low CO2
Green: balanced - enough CO2 for plants, not too much to suffocate fish