How to Make an Air Pump for a Fish Tank
- 1). Remove the plunger from an insulin syringe and discard. Leave the hypodermic needle in place.
- 2). Push the 1/4 inch transparent plastic pipe approximately 1 inch into the back of the syringe (as if it were a plunger) and secure it in place with a small amount of non-toxic 100 percent silicone.
- 3). Place the syringe and pipe on one side to dry for 24 hours. Push the 2 inch rubber pipe approximately 3 inches into the “mouth” of the balloon and secure the pipe in place with two plastic cable ties.
- 4). Place a small amount of non-toxic 100 percent silicone around the mouth of the balloon, where the rubber pipe has been secured. Put the balloon and pipe connection on one side to dry for at least 24 hours.
- 5). Place sufficient duct tape around the “free” end of the 1/4 inch transparent plastic pipe, to make for a snug fit once this pipe is pushed into the free end of the 2 inch rubber pipe.
- 6). Place the 1/4 inch transparent plastic pipe and syringe on one side, once you are certain that this pipe will fit tightly into the 2 inch rubber pipe. Attach the bicycle pump to the 2 inch rubber pipe and inflate the balloon.
- 7). Hold the end of the 2 inch rubber pipe closed with your thumb and forefinger so as to prevent the air escaping and attach the 1/4 inch transparent plastic pipe and syringe as quickly as possible.
- 8). Rest the balloon on the aquarium canopy and push the syringe through a “feeding” hatch into the water. Air caught within the balloon will escape through the needle on the syringe creating a stream of bubbles, exactly as an air pump would do. The tiny gauge of the needle means that the balloon will empty very slowly.
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