And if you haven't put it in use yet..
you might want to replace your bubble trap(tower) with plexiglas or acrylic. Make it higher than the triple bubble walls. And at the bottom 2 inches make it egg crate. Then fill it with rocks.
This way the bubbles would have to make it all the way down to the bottom 2 inches of the bubble tower past all those rocks.
The way it is now, the bubbles will flow right out of that eggcrate bubble tower.