so the past couple weeks I noticed my overflow box wasn't working right. my water level was much higher than usual I was about to overflow. I thought maybe it was plugged or my aqua lifter wasnt working right. So I took the lines off the aqua lifter about a week ago and blew in them and it seemed like it freed something. Put it all back together everything worked normal again. Few days later same thing... started to worry cause the water level was at the rim. Did the same thing. Back to normal. Well tonight I noticed it higher AGAIN. So I'm like ok wtf. Took the overflow off cleaned it all out cleaned the air lines etc.. etc... well this time the water level didnt go down... its suckin all kinds of air out of the siphon but there is still a bunch in there then I get to looking and the box is tilted... I'm like wtf? So I look at the other side and I find my problem. When I put my new powerhead in the magnet on the backside was between the overflow box and the tank which tilted the box and didnt allow the aqua lifter to reach all the air and get it out. I didnt think much about it when I put it on but I'm glad I caught it before it caused a flood!
Fixed in the pic but u get the picture lol.
Moral: pay attention when changing anything on your tank