Two more things about eheims: 1) If you get them off craigslist, you'll spend about half as much as if you get them new. Still a chunk o change, but not ridiculous. 2) When you factor in that you only need to change a little of the media every 6 months (for the classic canisters), and the media you change out can be bleached, boiled, rinsed, and reused, they actually pay for themselves in a couple of years.