I was doing the same thing you are. Adding just enough bleach to not do any good.

I'm betting if you increase your bleach dose to 10-15 gallons instead of your normal 6 you'll see an immediate improvement. Right now you are just spinning your wheels.

I had to add TEN of the large jugs of Wal Mart brand Bleach before I turned the worm in my favor. After that it was pretty simple. I measured my FC at 50+ on the first day, but by day 2 it had fallen to 15 ppm. So the bleach was being used up.