I used some brass fittings on mine and I have not had any problems.
As for the clear PVC, I used the clear PVC from the Python gravel tube. It is 2" diameter and thickness feels pretty good. I guess if you can get that part cheap in your area, it might be an alternative. Just an idea.
I just finished building one of these. I used the clear plastic tube from an old python. The insides of each end piece that the python went into had to be grinded down a tiny bit to make the plastic fit right. In total the whole thing costed me $12 canadian. I just started it up an hour ago. It built up a pocket within half an hour that I had to burp out manualy by turning the whole thing upside down. But I think this was just the air from my new bottle of yeast and hopefully I won't have to do it again.
Built mine two days ago man what a diff works awesome, I built mine out of ABS can't see in so I just make sure my bubble counter is working I dont really need to sit and what bubbles diffuse lol. Thanks for the article I based mine of this and another. CO2 using two hagen canisters, cause they look pretty lol from 14ppm to 28 varying of course but nice real nice
Is there anyway to incorporate one of these on a wet/dry filter? Any ideas anyone?
I have a spare pump laying around so I could theoretically build one that has its own pump and have the return going into my sump to be blasted back into the tank...