I received my AC50 yesterday and started to mod it for a refugium. When I cut the basket up into 3 pieces and go to insert the piece that goes goes between the impeller and the rest of the filter my piece won't go all the way down to the bottom. It stops right at the top of the teeth that keep the basket off the bottom. The only way I can get it to go all the way down is to put it at an angle, which I don't really like. I'm trying to put this piece about 1/2 inch from the wall so I can put some floss or foam in there before the chaeto. Am I missing something here?