sumps and refugiums

[wingsfan]

Well I've been reading these forums for about a month now and actually thought i was learning something,,,,,,then while trying to explain a little to the gf,she comes up with the question ------what is the differance between a sump and a refugium?, boy did i feel like an ARSE Hole when I didn't know how to explain it to her,,, Can some one help me and her out here? Exactly what is the differance? And i told her i been staying up at night to learn al i can,,,,now she thinks i'm lying??? :D ??? ???