I use two plastic straws with diameters of 7 and 8 mm.\r<br>The thinner straw fits freely inside of the thicker straw.\r<br>The standard 5 mm diameter air tube fits freely in the straw.\r<br>Lets build a telescopic tube.\r<br>Wrap a couple layers of cotton sewing thread around the thin straw, making a ring, about 1 cm wide, closer to one end of the straw.\r<br>The thin straw should fit firmly inside of the thick straw.\r<br>Loop a rubber band on the thin straw to make a stopper.\r<br>Take a small plastic bottle with a cap.\r<br>Cut off the top of the plastic bottle.\r<br>Trim off the edges.\r<br>Cut off the bottom of the plastic bottle.\r<br>Trim off the edges.\r<br>Cut a strip from the edge to the center of the bottom part.\r<br>The cut should be wide enough for the air tube to pass through it.\r<br>The bottom part should fit inside of the top part of the bottle.\r<br>Make a hole in the cap using a hot soldering iron.\r<br>The telescopic tube should fit freely through the hole in the cap.\r<br>Use a needle, a nail, or a hot iron to make little holes about 1-2 cm above the cap.\r<br>Holes prevent water overflow.\r<br>Lets assemble all pieces together.\r<br>I use padding polyester to filter fish poop.\r<br>Wrap a strip of filtering fabric around the thin straw.\r<br>Push the roll in the cap.\r<br>Move the rubber band stopper to adjust the height - the straw should protrude above the roll.\r<br>Insert the air tube inside of the thin straw.\r<br>Put the telescopic tube in the aquarium, burying the bottom end in the gravel.\r<br>It prevents any fish from getting accidentally pumped out.\r<br>Connect the air tube to the air pump.\r<br>Turn the air pump on.\r<br>Move the air tube slightly in or out of the telescopic tube for a better pumping effect.\r<br>Cover the filter with the bottom part of the bottle to prevent water spills.\r<br>Rinse the filtering fabric under running water once a day. \r<br>And then you can reuse it.\r<br>It is possible to use many commercial filters instead of padding polyester to remove unwanted chemicals.\r<br>This system can be used for filtering water, increasing oxygen level, and cycling water in any aquarium.\r<br>This is an example with 10 gallons aquarium.\r<br>Attach a paper clip to the rim.\r<br>Push the air tube all the way through the telescopic tube. \r<br>Then, pull it back inside.\r<br>Feed the telescopic tube through the handle of the paper clip to secure the top of the installation.\r<br>Bury the bottom end of the telescopic tube in gravel on the bottom of the aquarium.\r<br>Attach the air pump and turn it on.\r<br>Put the cover on top to prevent water spills.\r<br>Here is another example.\r<br>I use a plant holder of wire to secure the installation in the middle of the aquarium.\r<br>It creates slow flow cycle.\r<br>Have fun and happy fish :)\r<br>\r<br>Blog: \r<br>\r<br>More fun on my website \r<br>\r<br>Views as Money:
