Sounds like your going though a lot of time, energy and money, trying to track down the materials needed for Affnan's new design on his siphon.

I build the "Pipe Siphon by Apollo" and had it working in less than 20 minutes, just out of parts I had laying around. It has been working none stop for over 1 year along with the 2nd one for my other GB. I have not cleaned, tinkered with or even unburied either one of them since I installed them.

I have ran 3 different pumps, added vertigrow towers, whirlpool filter and a duckweed tank. In doing so have diverted pump volume and water pressure away from the Pipe Siphon. It has handled all changes without missing a cycle.