Coating your prop to stop growth doesn't work for me

OK remember back in October before splashing, my prop looked like this.

Normally it is bronze colored, but i had a zinc coating put on and sprayed never wet on a dozen times to try and stop algae growing on it. This was less than 4 months ago. It had been not too bad up to January but this morning I decided that enough was enough and I took to it with a brush. This is a photo after I had brushed it.

Other cruisers have reported good results from prop coatings so I can only guess that because I have been in certain areas and done a lot of miles, that it doesn't apply in my case. Anyway,  this green stuff has to go somehow or other.  It is incredibly tough to remove with a brush and I am trying to figure out if there is a way of somehow putting bleach on it because growth just disintegrates when it comes in contact with chlorine.  Ideally I would like to cover it with a plastic bag, inject bleach into it and then let it sit for 5 minutes. Then brush it to remove the dead algae. I am wondering now if there is a product that you can coat your prop with that has slow release chlorine similar to the slow release copper in our bottom paint. Mmmmmmm.......

Anyway, after thinking about it, I came up with this solution.

A rag on the end of a stick dipped in bleach to rub on the prop. Here are my results.

A little bit better but not a perfect solution and at least it gets me mobile again. Take a look closely at the next photo where you can see the zinc coating has come off and the bronze prop showing through.

My guess is that somewhere along the line, my prop must have come in contact with a fishing line or some hard physical object that has scraped the coating off the prop.

One piece of good news is that the rest of my hull is quite clean with not too many barnacles on it. I used micron 66 which was very expensive but now I can say that it was worth it.