Just add citric acid, baking soda, water into the bottle, can produce carbon dioxide. The plant metabolic rate can be increased quickly, create the best growing conditions for fishes. It is the best choice of making CO2 equipment at home. It is easy, safe and economical. Raw material ratio£º A bottle: Citric acid 200g+water 600g; B bottle: Baking soda 200g+water 200g. Features: Be made of aluminum alloy. It is strong, durable and efficient. Well-sealed caps and pipes, leak-proof, non-deformed, never loose. Professional pressure guage for pressure watching. Cheap, simple to create pure CO2 constantly by chemical reactions. Bubble counter with check valve: Flow-rate of CO2 gas indication device and prevent water flow back into the bottle. Equipped with a safety valve, the pressure is greater than 4kg pressure will relief automatically, carbonated beverage bottle pressure is 8kg, safety is ensured. The safety valve supports manual pressure relief. When the pressure is below 4kg, it can
