When I first started keeping tropical fish i used to use a gravel cleaner every week and had trouble with cycling my tank, my plants wouldn't grow and I lost the occasional fish through bacterial infections. It was suggested that I don't use a gravel cleaner unless you could see a build up of unslightly fish waste on top of the stones and even then only syphon that off. Then instead just do a water change.
Well I've been doing that instead now for 6 months and my plants are growing, I have not had any fish losses related to bacteria and my tank still looks really clean as all the fish waste is breaking down. (and I haven't had to syphon any off the top either)
So if you are fed up, my suggestion is to stop cleaning your gravel for a while and just do a water change. You might be surprised at how easy things become. I was.