I have had a metal trash can as my collector for a while now. I think it it is letting air in and thus chips going in my filters. I want to replace it., It is 26.5" tall. ClearVue does not sell bins(best I can tell) but PennState and Oneida do. I am looking at a 35 gal system as the 55 gal are too tall for my set up. My question is on the Oneida system that comes with a flanged top, the options are for a 5" OR 7" or larger flange. On my ClearVue, the drop down is 6". Which should I choose, 5 or 7"?