Hello all! I need some help. I have just finished redoing an old 75 gallon tank I got and I am having some issues with my bulkhead. My set up is as follows. I installed an internal overflow box at the top of my aquariums. In this overflow box I have a 1 inch bulkhead that has an elbow screwed into the outside edge. I have 1 inch pipe hooked to that elbow and it flows down to the sump. Now the problem is that this drain system is sucking a TON OF AIR and it is making a loud slurping noise in the overflow box. How can I fix the air in my lines and stop the slurping noise? Thank you for any help you can give me!