Overflow BOX

[Aquamann88]

Anybody an idea why my second u tube on my overflow box is losing siphon.

 

[JC1977]

Off the top of my head I would say you’re not pushing enough water with your return pump or pumps to keep the siphon going and free of bubbles.

 

[Minifoot77]

How many tubes are in that model of over flow? 3 or just the 2? Mine that has 2 I use the 2nd one to regulate the height of the water in my over flow and it barely trickles