CO2 Long Acting Monitor Drop Checker with Suction Cup for Aquarium

This CO2 long acting monitor is a drop checker for aquariums, used to keep an eye on the carbon dioxide level in the tank. Add 5 drops of the included test solution, then refill aquarium water up to the water line. The colour of the liquid shows the CO2 status: blue means insufficient CO2, green means normal, and yellow means excess CO2. Made of clear glass with a wide channel and a strong suction cup, it measures about 4.2 x 2.5 cm. Note: new and old types are sent at random.

What's in the box
1 X Carbon Dioxide Detector, 1 X Test Solution 15ml