Scenario:
I had some plumbing redone.
Definitely had reduced flow, tank went real nice and quiet.
But within 2 weeks, had some hair algae grow.
Checked flow coming from the tank. It was at 165 gal/hr.
I increased it to 450gal/hr, but the durso had some back pressure and was gurgling like crazy.
I backed it down to 260gal/hr and left it there.
You are saying 390-650gal/hr?
If so, how to release that pressure? Drill bigger hole in the durso? or just live w/ the gurgling.
And just to compound the problem, i was away on vaca for 1 of the 2 weeks, and the phosban blocked up.