I have a 92 champion and the aerator doesn't appear to work on it. The fill works and if in free flow (valve open) it fills as well, but no aeration. I can not find the aerator itself. In the livewell their are two pvc pieces, one on each side, the one on the starboard side say aerator on it, but this looks like just a tube, not the aerator pump. Where is the aerator on these?