Questions for those who have a HOB U-tube type overflow.

[hawk]

I had a lifereef overflow. The tubes were in a overflow box inside the tank so the water level never dropped below the tubes. So even if the tank water level dropped during water changes the level inside the box never dropped enough to break the siphon. The siphon would stop (but not break) when the return pump stopped (power outages, etc.) but always started when the flow started again. The only time I ever had to restart the tubes was when I took them out for cleaning. As for noise it took some occasional tweaking but for the most part was quiet.