Quote Originally Posted by flienlow
from my experience, the hole size doest matter. The water dips to a certain level and stays there. I have 4- 3/4" holes on the cap pipe. More than enough.

But thank you for sharing!
Of course it matters! Where the air holes are in relation to each other can have an effect too. Ideally, you want it configured in such a way that the maximum air gets introduced into the pipe at one time otherwise the force of the vacuum will pull more water and continue the siphon (not what you want). YouTube fluid mechanics. There are a lot of basic conceptual videos that will give you an idea of what you're doing.

I can't really see the bell siphon from your picture, but it looks like you have several feet of pipe after the bell siphon... LOL! Even if the siphon gets air in the force of the water siphon in the rest of the tube will keep the siphon going. That means the water flow is about right for this condition. You probably hear a "gurgle gurgle gurgle" sound but it keeps on truckin' right?

Get a better picture of your siphon. It's impossible to guess what you did based on your description. You probably want a T fitting near the top of that long tube so that it doesn't make a siphon, but even then you will have some force from the resulting pressure differences.

Good luck!