Wow! I've hardly ever had any problem with my Eheim filters. I've used their canisters as well as the internal pickup variants and I've been more than happy. I find they aren't the best if you're looking for crystal clear water, but as a biological filter I have 0 complaints. The only Eheim filters I personally can't stand are their Aquaball ones, they really do get clogged after hardly any use. :\ They've got ones out now called biopower that look similar, haven't tried them though as I was so disappointed with the Aquaball...