Thanks for making the pictures bigger, I did try to click on them but I thought originally I was doing something wrong. Is that first picture the reason you were suspicious? Or did you just go to clean out your filter and... surprise!
Yeah, that line of ants was the first sign and then I followed them to my filter. I noticed they were getting into it so I took it outside and popped it open. then I found the ants crawling all over the the hollow space around the seals so I disassembled the power head's casing and HOLY S@%#!