I think I was also able to pull up cobalt jellies in Selbina using a sabiki rig and carbon rod.
Be careful using carbon+lug worms in Selbina, as some of those salt water fish can get pretty big and they'll bite on lugworms. I've broken my carbon using that combination before.
I think sabiki rig will only catch small fish like bastore sardines and quus, and the occasional jellyfish. I don't know if there is a specific lure/bait that you can use that only jellyfish will take.
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