Three things that I know work. High dose of chlorine (10 PPM - will clear but takles a while), enzymes (works well but is slow once there's cloudiness - more of put in before and let them work as needed) and clarifier (this takes about 24 hours to work). Or a combination of chlorine and clarifier - just be fore warned, clarifier can foam. And Filter, Filter, Filter!!!
If the water is real mucky then hit with chlorine for a few hours then drain and refill.
As far as bleach for cleaning the filters - I've used it in the past. 1/4 cup bleach (I guess) to about 2 gallons water (I know real scientific calculations). I did notice after that the plastic on the filter was a little lighter in color, so I plan on using filter cleaner in the future.
Hope this helps!