Skimmer bubble height?

[Auqaman]

Hi everyone,
I’m having a hard time understanding where the bubbles should be in my protein skimmer. I heard that “at the base of the collection cup” is a good starting point.
But how does it fill the collection cup? Will it fill the cup automatically if there’s pollutants? Or do I need to open the flow valve to fill the cup? I’ve attached a picture of where I’m sitting at now. I’m still cycling the tank, so I suppose there isn’t much pollutants to remove.

Thanks

 

[S2G]

Personally I start at the base then go from there. Once you have more nutrients it will get dark & bubble up more. Then you can tune it to skim more wet or dry

 

[WVNed]

When a skimmer is running in tank water that isn't new inside the body will form into 3 sections once the skimmer is broken in. The water at the very bottom will be clear with no bubbles in it. The water in the middle will have water with bubbles mixed into it and be white. Above those 2 a foam will form.
You want the interface between the foam and the water with bubbles in it about at the bottom of the collection cup on your type of skimmer.
Until you get a feel for it unplug the skimmer and let it set for a minute and then restart it. The water will rise with the bubbles in it but no foam over it. Use this to set the running water level at first.