Hey Guys
I know this is an old thread but I've recently been considering some mods to my last skimmer design, a BK Mini-200 knock off with a recirc mod,...
and this subject has been on my mind. Specifically, I'm considering switching to single pass.
Allowing for the higher water:air ratios the newer foam pumps (Red Dragon, SICCE, etc) produce I see that, from the perspective of the foam pump only, recirc doesn't have an advantage over single pass.
However, I noticed in my testing that the higher the venturi head pressure at startup the lower the max air draw. In other words, if you start a skimmer empty the max air draw will be higher than if you start it full.
As I was filling my skimmer the air draw increased. It peaked at around 8". At around 15" it started to drop off. I realize the levels will vary by pump but the trend held across all the pumps I tested.
Do the recommended water levels for single pass skimmers take this into account?