G'day mate
Sorry to hear about the lack of fish! All the waterways around Brisbane should have something to offer anglers. Some locations wont have a great range or size, but should at least have something! I don't know of any waterway with no fish, and refuse to believe such a waterway exists, particularly tidal zones!
Perhaps let us know what you have been trying? Details of the location? What tides, structure, time of day etc? Other members might be able to offer some advice or suggestions/ideas to try for next time.
Sometimes fishing is tough, others its easy. When the fishing is tough, its those anglers who are willing to try new things so work out what the fish will eat that typically end up with the fish! So hopefully we can throw up a few new ideas for you?
Cheers,