Skimming outdoor air

[lars]

For those of you who ran your skimmer air line outdoors to raise pH I have a few questions. First is did you go with a larger diameter line to make up for the length added? I didn't know if adding length to the line if there would be less airflow to the pump for skimming. Second I was wondering if you removed the muffler? I figured it wouldn't be needed and would once again add more resistance to the line.

 

[nervousmonkey]

Howdy Lars, I increased the diameter of the line to allow for an increased total volume of airflow. The airflow rate is a function of the velocity of air in the line multiplied by the (inner diameter/2) squared, so the I.D. of the airline has a huge effect on the air flow rate through the line. Length of the airline doesn't play a role in the airflow rate, but length plays a very direct role on pressure loss, so based on those two equations (air flow rate and pressure loss, through a pipe, line, tube, etc), the I.D. of the line should definitely be increased so there is a small to no effect on the air flow dynamics of a venturi skimmer, which works based on very precise allowances for water and air flow rates as well as pressure.
I removed the muffler, not because I thought it would add resistance but because it is unnecessary, although I am sure that it does add some resistance.

 

[hawkinsrgk]

I went from 3/8 to 1/2 line and have just finished the setup within the last week. In my case the skimmer to the outside wall isn't over 3 feet. I also removed the muffler