Following along as I just bought a new tank / Nyos 120 and hoping to find all the "answers" to the problems i'm sure i'll encounter. Would love to know how long it takes for the skimmer to calm down....
I have a NYOS 120 (and 160) on my tanks. They will bubble out the bottom and overflow when new. Break-in period depends on different factors. My one tank had natural live rock and break-in was a few days. The newer tank with the NYOS 120 had Caribsea Liferock... that thing bubbled over until after my 3rd water change. Also water level matters. The sweet spot I found for water line is in the letter "Q" on the logo of the skimmer. Hope this helps. It's the best skimmer I've had now.