Printable airlift underground filter

A ground airlift filter for 40...200L aquarium.
That's you need:
- Two standart 0.33..1 L PET bottles. If you have a big aquarum, or there will be lots of fish, bigger bottles recomended. Sure that you can put bottles into the aquarium ground, and it will all hide. It's good that your ground depth is 10 mm or more bigger then bottle diameter.
- Any 25mm/1" tube, 100mm less length than your aquarium height. If you want a powerful filter, you can use two tubes and two compressor. I use a chemic