I do not agree with the common practice of cleaning mechanical media with tank water. I prefer to overload my filters with bio media, which gets rinsed with tank water 3-4 times a year. The mechanical media gets rinsed with hot tap water once a week. I do this for 2 reasons. 1 I dont know about your guys mech media, but mine after a week is so gross it takes some pressure to get all that gunk out. 2 I dont want a significant amount of bio bacteria in y mechanical media. With 2 litres of biomax, 2 litres of denitrate, 24 bio stars, and 2 biowheels, I want most of it in the expensive biomedia. With 4 large filters for my 55 I have never had a min cycle or problem cleaning my mech with tap.