Printable airlift underground filter

thingiverse

You need a ground airlift filter for your 40...200L aquarium. To build this, follow these steps. First, you will require two standard 0.33..1 L PET bottles. If your aquarium is large or you have many fish, use bigger bottles. Make sure the bottles fit into the aquarium ground and blend in perfectly. The bottle diameter should be smaller than the ground depth by at least 10 mm. Next, find any 25mm/1" tube that is 100mm shorter than your aquarium's height. If you want a powerful filter, use two tubes and two compressors. I use chemical glass tubing. For bacterial housing, use aquarium filter ceramic cylinders or other porous materials that won't obstruct the water flow. Place these materials into the bottles. Two standard aquarium airstones, with diameters of 20-25 mm in shape or spherical are good options. If using just one tube, air stone can clog or break so having two is always a safe option. Even though one 25mm tube will do, use two for maximum benefit. A silent and powerful compressor that can handle 100-150 liters per hour of airflow is required. Now, print the filter parts using high-quality material like PETG instead of PLA for longer-lasting performance. If you're only using one tube, print the tip only. However, if you opt to use two tubes, then print the corner pieces. Avoid using light colors for these as they may appear dirty over time. Perform many small holes in both the bottoms and sides of the bottles near the bottom, preferably not in rows so they blend into ground. Use a dremel, drill or soldering iron for best results. Each hole must be slightly smaller than the fraction of the sand your using (about 1-2mm is good for 2.5-3 mm) but more then this would be bad as it would let the ground just get through so more than a little more than one hole will help here. Put the ceramic cylinders inside each bottle, giving them complete space so there is not room for bacterial development that might contaminate your filter.