Well, I'm not sure if anyone else has done it before but never fill your res to the top while the pump is running. I was merrily filling it up and when I got to near the top, I decided that was it. I turned off the power and the pump made a weird noise before a spurt of coolant flew up into the air through the res fill port (some got onto my tongue, nasty propylene glycol). I was stunned for a few seconds before rushing to clean the mess up.