The Aquarium CO2 Testing Solution is designed to accurately monitor the carbon dioxide level in your aquarium, ensuring a healthy and thriving environment for your aquatic plants. With its high precision, you can easily adjust the CO2 supply in your aquarium to maintain optimal conditions. Features -Color:Multi -Material:methyl blue -Size:7.70X2.10X2.10cm/3.03X0.83X0.83in -Note: 15ml, no need to mix with tank water; Green: right balance of CO2; yellow: too much CO2; blue: too little CO2 -Accurate monitoring of co2 levels in aquatic environments to ensure a healthy ecosystem. -Efficient measurement and precise display of co2 levels for easy monitoring and maintenance. -Long-lasting usage of the co2 monitoring liquid for cost-effectiveness and prolonged effectiveness. -Easy operation with instant results, allowing aquarium owners to quickly assess and adjust co2 -Suitable for a wide range of aquarium types, ensuring compatibility and effectiveness in various aquatic setups. Package list: 1 x bottle of indicator solution