I'm starting to run low on cartos and I want to try Boges. Question is my tanks I have are the Volcano Tube tank and they both use the Mega size carto with the flange at the bottom.. Problem is I cant seem to find Boges like that.. Is that flange that important.. I don't have an issue with the Volcano cartos at all, price wise they are cheap and work fine for me but I want to find a supplier that's a little closer.