I found one thread that mentions a guy using an airpump to pump water... apparently they last forever and wont burn up if the rez ends up dry.

How big of a space do you have to work with and how big will the reservior be?
Fine questions my friend... I have ample room next to the tank for a cabinet so I could go big if I wanted to but I think I'll try to stick to 10-15 gallon reservoir with enough room to fit the skimmer. On top I may set up a speciality tank/QT tank/fuge... I dont know, maybe just a place for my books and fish stuff