herbie overflow ?

[WarDog]

How high is the valve on the main drain? Ideally, herbies run best with the valve low, so the entire run is full of water. If it's not full of water it's full of air...

unless you're Frank Borman, then it's full of stars.

[donkey77]

its just a little lower then the overflow

[mihaivapler]

Originally Posted by donkey77

its just a little lower then the overflow

I have same drain type but the valve is right before the water enters the sump,as wardog sad you want to have your main drain full of water at all time,and also the pipe in the overflow to be about 1 1/2" lower then the water line otherwise it might such a bit of air from the top.that happened in my tank,had it only 3/4" lower and the water draining down would create kind of a spiral and would suckered the air to ended up with bubbles in the sump..