my friend and i caught two kole tangs (about 4-5") using different methods: "the trap" by ultralife and a small fish hook with a crushed barb.
my friend tried using "the trap" but didn't work....more on it later.
since the trap didn't work for him, i got him some small fish hooks, size 18 or 20, split shot weight and clear light weight fishing line from a camping store. we used a plier to crush the barb in to minimize injury when removing it from the fish's mouth. put it all together and went fishing. biggest problem was other fish kept taking the bait. so we had to feed other fish and used tongs to chase away the tang so it'll be hungry enough to bite the hook after all other fish are fully stuffed. it took him several days and lots of patince to catch the tang.
i caught my kole using the trap. the instruction on the box said to set it so that you pull on the clear fishing line to open the trap door and release the line and the weighted door will close on its own. that doesn't work!!! the door kept getting jammed and wouldn't close. you have to thread the line thru the hole on the body of the trap so when you pull the line, it drag the door down to close the trap. the first night i set it up he wouldn't go near it. i put a small tonga branch rock on top to keep it near where i normally feed and left it there so he will get used to the object. the next day i didn't feed until night time to keep him hungry. propped the door open, squirted thawed mysis in, the tang and a wrasse went in so i just trapped them both.
yes both methods took time and patience. i thought the trap was easier than the fish hook but you gotta modify the method a bit. hope this help.