I have found that with the jewies I like to fish the bottom of the tide when the water is really brown with livies. The pipeline has been the most productive place for me with this technique, although I have lost a fair amount of tackle on the pipe!
I have got them to 85cm on live herring off the pipe. I wouldn’t be to worried about the size of the livies, as Craig has said before fish will eat a 40cm pike so I would think they would easily eat a 20cm mullet.
If you fish over the pipe I would use heavy gear. I used to run a 60 pound leader when I fished on the pipe purely so I gave myself a chance.