I have the 65 version on my 29 gal
When its working properly, the water line should be right at the base of the upside-down-tornado-lookin-funnel-thingie. This way the bubbles start to collect and move up the inside if that funnel.
if foam bubbles up too much, turn the red knob to the thing flows less, you basically want foam in the funnel to struggle to make it to the top. thats where I get the best collection. If foam easily gets to the top, i get too much overflow and its really watery.
so were clear... the unit is infact making microbubbles right?