Review on EHEIM Professional 3 Thermofilter 2180: Powerful External Canister for Large Aquariums up to 317 US-Gallon Capacity by Breanna Homack

Love it! I've had it for several years with no problems. I have found that it works best as a biological filter and does not require chemical filtration. Every few months I change the disposable filter element to avoid unnecessary stress on the pump and I clean the heating element, but other than that I just leave it alone. If you want a crystal clear aquarium, do regular partial water changes and get a good reverse osmosis filter to put on the tank overnight once a week.