Last summer I went out on the Big Ta Do out of Port Allen (google deep sea fishing kauai for website). Port Allen is on the SW part of the island. I went on an afternoon half day trip with Captain Justin. The big tuna were close in and we were fishing as soon as we left the harbor. There were three of us fishing on a shared boat. We hooked an absolute monster YFT right off the bat and took turns fighting the fish because the guy who hooked it got too tired to continue. The deckhand Brandon was a stout guy who had played college football. When he gaffed the fish it turned its head and took off almost pulling him into the water so he let go of the gaff. That fish broke the super heavy mono leader and took the gaff and lure never to be seen again.
We caught a few smaller fish and had a good time. We all got plenty of fish for the barbecue to take back to the condo. I would recommend this outfit and would go with them again. Good Luck.
The best food we had on the island was at koloa fish company, a little take out place in Koloa Town.