5 Year Member
I made this air-powered internal filter from a plastic jar (Archer Farms Peanut jar from Target), needlepoint screen, and plastic pipe. Cut the top off the jar so that the jar lid will fit inside it, drill or cut several holes in the lid, glue the lift pipe over one of the holes, cut a circle of needlepoint screen to lay on top of the lid, and cover with media of your choice (lava rock, gravel, carbon, aragonite, polyether foam, etc). I used a "Jetlifter" pipe from Swiss Tropicals, which has a nipple to attach airline, but plain PVC would work too, with airline tube inserted down inside the uplift pipe. The Jetlifter has tiny air holes that make smaller, quieter bubbles. I used "Shoe Goo" or "Goop" to glue the uplift pipe to the jar lid. This lid is polypropylene (PP-5) as indicated by the recycling code; some glues including silicone will not stick well to it. For PVC pipe, adding a coupler on the bottom will give a wider surface for the glue to bond. Filter media in this one is a mix of old Jungle brand filter carbon (USA) - no longer sold as far as I know - plus small lava rock. For non-blackwater fish I also add aragonite (crushed coral).