I built it over four years ago and can't find the paper work where I got the water filter container. Just find a 20" clear filter with the RED air release button on top and 1" pipe inlets on both sides. The other item you will need is a brass air hose nipple with hose barbs on one end and threads on the other. Drill a hole in the inlet side PVC pipe and screw the brass fitting in. As for the inside, cut a piece of 1" tubing that will go from the top lid to the bottom of the container. Mine slipped right on to the bottom of the lid. No clamp or zip tie. I'll post some pictures that will help you with the rest(can't attach to message). Let me know if you need any more help.
Hi CL, I just happened to notice your picture of the FX5 and your homemade CO2 reactor. I can't seem to find this in a thread. do you have any more info? I have a similar tank (100G) w/ pressurized CO2 system and seem to keep investing in a diffuser collection. Your solution looks pretty simple. Thanks, Patrick (Pondfrog01)