Regretting having an emperor 400 on with my tank. The cartridges need replacement ALL THE TIME. flow slows down and it goes over them or backs up and goes other ways. And the cartridges are NOT cheap? Another option? Its a piece of work. Touch it and the impeller makes loud noises for a week. Turn it off for stuff and it makes your water all nasty when the water goes back down or when turned back on. It'll randomly have a really loud impeller. Might just remove it and turn up my canister flow rate. But are there other options for rite size E cartridges? Can i just clean the cartridges?