Sorry if this thread already to the forum!

I've been having some issues with bell siphons. They start to drain, and you can hear them struggling to pull up air when the bed has reached low levels, but the siphon does not stop. There is a consistent, long trickle afterward (which stops after being adjusted).

I have adjusted the water flow, the length of the snorkel, and cleaned the piping but I'm unsure of what to try next. Does anyone have any suggestions?

Thanks so much!