I spent 2 years in casino up until June this year, there are some pearch, heaps of mullet and carp. Also dont go in the water as there are alot of bullrout in the richmond river. If i was you i would head to Evans Head, its only 45mins and really good whiting and flatty at this time of year in the big hole next to the bridge.
If your really after fresh water fish the weir at casino is your best bet, also there's a street on the right heading out of casino towards Lismore on the bruxner highway about 1km past the the car wash, follow that till you get the to the river theres and old dock from when the barge used to run. Toonunbar Dam out the back of Kyogle also produces nice yellow belly and bass.
cheers, Neil