Vertex skimmer IN 280,problem solved,thanks mojo for your help. The airline was clogged so unclogged it and off to the races of fine bubbles again to the top of the cup. I had this skimmer for 2 to 3 years now with no issues except the impellar,its in my 40 gallon long sump,had to relocate my fuge because of the skimmrs size. My friends joked me of fitting a shark in the sump,it is a beast but very fitting for a 300 gallon volume system. Happy with it and with heavy bio load reef tank,he carries his weight because tank is crystal clear and everyones happy. I am joining the club with the vertex IN 280,will glady post pics soon. Its nice to tag along this vertex club to see everyones thoughts and ideas of new mods.