I have 2 on my 55G. I replace the filter pads when they clog up, and only check the baskets, which have ceramic cylinders and lava granules. If they look all gummed up, I rinse them off and clean the basket itself. As for cleaning the filter itself, I clean the housing, a complete teardown, about once every 6 months. While doing the teardown, I put the filter pads, biowheels, and baskets in tank water, and clean the filter housing under the sink.