Description: Too much or too little CO2 can harm your aquatic ecosystem and affect the health and growth of your plants and fish. This simple device allows you to monitor the CO2 level in your tank without any hassle. You just need to fill it with the included solution and hang it inside your tank. The solution will change color as the concentration of dissolved CO2 increases or decreases in your water. The best part is that you don't need to consider the ratio of water to the solution, as this drop checker is calibrated for use in any water condition. Whether you have soft or hard water, low or high pH, this drop checker will give you accurate results. With this CO2 checker, you can enjoy your planted fish tank with peace of mind, knowing that you are providing the optimal environment for your aquatic life. Specification: Name: Fish Tank CO2 Glass Monitor Condition: 100% brand new, high-quality Detector product material: glass Ease of use: Make sure your test suite is clean. Put 5 drops of CO2 indicator into the glass drop checker and make sure to store it on the ball side of the with the opening facing down. Place the suction cup (included) on the droplet and attach the CO2 droplet checker to the side of the tank, submerging it completely in the tank water. Wait 2 hours for the CO2 level to be read. Product List: Detection solution*1 Detector*1 Suction cup*1