I have had my current tank for roughly 2 years and in that time period I have gone through 4 submersible pumps. 2 rios and 2 quiet one 4000's. My second quiet one just died and i'm starting to get quite angry at pumps in general. Is it possible that there is something specific about my setup or possibly even the wiring in my house causing these pumps to die or am i just freakishly unlucky? I run them as a return on my 75 gallon with flexible tubing.