Back in the early nineties a friend and I went to Guatemala on a three day fishing trip.  Sailfish fishing at the time was incredible. Killing a sailfish was strictly forbidden.  An armed military gun boat checked you in and out of the harbor each day.  There were so many sailfish that it was like fishing for schooling bass.   They would troll teasers with no hooks to raise fish.  With a fish at the back of the boat, you could choose which rod and bait to use. We caught over 60 fish in all.  The last day we grew bored, so we started catching them with light tackle.  I had brought an Ambassador 5500C loaded with eight pound mono.  After two hours, I landed this fish, took this photo and released it.  Much of the fight was recorded with a VCR camera. This fish was estimated to weigh around 120 pounds.  I checked with the IGFA and it would have been a world record at the time. Lots of crazy things happened on that trip....

 

No weights but I've had some huge stripers caught on a ML spinning rod and 8lb test with a fluke.

Well I think @Captain Phil wins 

7 minutes ago, TnRiver46 said:

Well I think @Captain Phil wins 

These days I do not recommend fishing for large offshore game fish with ultralight tackle.  By the time you get the fish to the boat, the poor fish is near death from exhaustion.  It may not be unable to escape from predators like large sharks.  

24lb 12oz striper on 6lb mono with a very jerky drag and a zoom finesse worm.  142lb swordfish on 40lb mono.  Many bonito on 4lb; tried 2lb but couldn't land any.  Mitchell 308 reel.  Captain Phil wins.  

I tried 2 lb myself once.  It's like sewing thread.   Very difficult to get a hook set.  The biggest LMB I ever caught on light tackle was an 8 on 6 lb.   I was fishing in Okeechobee with a 3" Rapala when the big fish sucked it in.  To land a large offshore game fish on light tackle requires a very skillful boat captain and a lot of luck.  I had both.

That's a great photo of a happy kid! Congrats!

 

For me... most memorable: A 9lb rainbow trout on 1# Trilene XT -a 2kg "class" line, to break at under 2.2lbs, on a 6ft graphite rod built for that purpose (on a 1970's Exxon blank -one of the very first graphite fishing rod blanks). Took 10min on a watch, with numerous leaps that had me "bowing" to the fish, hoping it wouldn't land on the line and break it. Learned a lot about being tethered to "motivated buoyant hydrofoils".

 

Bass: A number of 4lb LM's on 4lb "test" (designed not to break under 4lbs).

 

Most recent: A 4.75lb LM on "6lb" test (designed not to break under 6lbs):

Picture doesn't do justice. She was thicker than a snicker. 6# test. Shallow pond. Had to walk the bank to wear her out

thats a beauty @Travis Lofton

4.75 lb walleye on 2lb test and a 26" ultra lite rod, through the ice of course. Best fight I've ever seen a walleye give.

39.75" northern on ul and 4# mono 1/16 oz jighead thin wire hook. 

 

Use to also carp fish with UL and 4# mono.  Caught a few 50+# grass carp on 6'6 m action and 8 pound co poly

I got a 8.6 pound bass on 8 pound test using a senko.

Also got a 22pound catfish on 8 pound line while bream fishing. A

And a 32 inch carp on 6 pound test.