First some info on how I do my filter media. I replace my mechanical/chemical filtration media in my HOB filter every 3 months. I rinse it every weak in chlorinated water then rinse it in de-chlorinator water to kill beneficial bacteria and remove the chlorine after so it kills the bacteria, I do this so the bacterial dependency is NOT in the mechanical filter but is in the tank and bio sponge where it should be. This makes it so when I replace the mechanical filter media I don't get a mini cycle since the bacteria dependency isn't in the mechanical filter. I know bacteria dependency is an arguable topic since most people don't think that far into it, but so far my tests show great results in an slightly overstocked tank. I mean really I have 0ppm ammo, 0ppm Nitrite and less then 3ppm nitrates with my nitrate reducer... Id hate to mess that up. But now my biological filtration is blocking the water flow making more and more water go through the over flow. I lightly rinse my biological sponge in dirty water change water once a month. But the thing is like a block of mud still. Should I slowly replace parts of it with clean media or should I rinse it harder and prep for the mini cycle with prime and a bacteria supplement? In a nutshell what do you do with your bio media after a year and it looks like solid mud?