nexberg aquarium air pump super quiet <35db mini piezo air pump for fish tanks up to 13 gal oxygen supply ultra silent nano energy saving 1w with free thermometer, check valve and more! nexberg setup instructions: ----read the user manual that comes in the box---- 1. connect the air stone to the air tube. make sure it fits well to prevent air leakage from the tube instead from the stone. 2. connect the air tube to the air pump outlet and also make sure it fits well and steady. 3. stick the sucking disc on the back of the pump. 4. if you are not using the check valve, install the pump above the water level to avoid any possible water backflow. 5. if you have to possition the pump below the water level of your fish tank, use the check valve to prevent water leakage through the air tube inside the pump. install the check valve as shown in the user manual(delivered in the box). 6. place the air stone in the aquarium tank, immersed in water. if the air tube is too long, cut a section as needed. 7. connect the power adapter to the electrical outlet to start operation. note: the air pump itself is not waterproof, please keep it away from water. put the air pump higher than the fish tank water level to avoid malfunction or counter flow. keep the air tube in a good layout, or you will not have a good bubble blast as you expected. package content: 1 x aquarium air pump 1 x suction cup for the air pump 1 x air tube 1 x air bubble stone 4 x suction cups for air tube 1 x aquarium thermometer 1 x user manual 1 x power supply adapter technical specifications: power supply: 110v power consumption: 1 w flow rate: 0.36l/min tank volume: up to 50 litres frequence: <50hz noise:≦35db pressure: 10kpa air tube length:1m power adapter cable length: 1m