I would say unless it is ceramic and titanium or at the very least stainless it would be a bad idea. I was wondering the same thing. Maybe call the manufacturer and find out. I know their web sight doesn't specify so it is probable fresh water only.
pond master is the same company as magdrive. I have the pondmaster 3600 on my tank.......Holy crap does it move water......but beware of the heat pond masters produce. If it is a smaller tank Id recomend a ehim pump......did I spell that right?