On 10 Mar, I saw a large floating platform about 5m x 5m, with bags of stuff under a tarp.
Oct 2014, when I was also regularly checking Lim Chu Kang Jetty after a mass fish death incident, I also saw biscuits being loaded onto a boat there.
facebook post about this blog post.
I also hear that some fish farmers use expired packaged carbo from Malaysia and Indonesia. So if we see packages of foreign snacks and instant noodles, these may not necessarily have floated all the way from these countries. [Update 26 Mar: Here's some packages of foreign snacks and instant noodles I saw at Pasir Ris]
Even though a skip tank is provided for Western fish farmers, and it is well used, it does require farmers to bring their trash all the way back to the mainland. Here's another old post about my efforts to address the trash issue with AVA.