Benefits of Using a CO2 Regulator in Your Fish Tank Plants Look Healthy. It is well known that fish and plants need a balance to coexist. Plants thrive on the CO2 produced by fish, while fish feed on plants and take shelter underneath them. However, too much or too little CO2 can affect both plants and fish. Symptoms of a lack of CO2 include pale leaves and stems or stunted growth in plants. It also means that plants are unable to properly aerate their environment or provide proper nutrition to fish. This negative situation can best be avoided by installing a quality CO2 system. Healthy Fish. CO2 plays a vital role in the life of fish. Too much or too little can not only harm fish, but can also cause premature death. Fish produce CO2 during the breathing process. Too much CO2 in the water can increase toxicity and affect pH balance. Unfortunately, unless you are very good at detecting or paying attention to CO2 levels, you will see sick or dead fish. A CO2 regulator helps regulate CO2 levels, minimizing the negative effects. Inhibits Algae Growth. Algae is one of the biggest threats to fish. This compound can affect fish life by creating an unhealthy environment, causing illness in fish and affecting other plants. Studies have shown that carbon dioxide can promote algae growth and can also lead to excess ammonia, which is dangerous to fish. Installing a carbon dioxide monitoring system in your fish tank can help combat the negative effects. Colour:As Shown Material:Metal Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on. voltage: AC220V Package Contents: 1 * CO2 Dual Meter Solenoid Control Valve Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.