First off, Haddock is not a fish found in southern waters cause it likes cold water just like yankees.
Second, malt vinegar works well with fish.
Get some Thai or cayenne type peppers. I prefer cayenne. Use apple cider vinegar, pour some out, add the peppers and a pinch of salt. Let sit awhile and just keep adding vinegar as needed to keep the peppers covered.
and remember............WE DON'T SERVE FRESH HADDOCK IN THE SOUTH, THEY LIKE THE COLD, JUST LIKE THE YANKEES
You are correct , no one can make a living up here selling air conditioners that's for sure. I just recognize ME, NH, and VT as Yankee Land, just one step over the NH and MA state line and I consider myself "Down South"
About that vinegar I used the White kind as we Yanks do put that on Dandelion greens and in NC. the pull pork places use the white with a green pepper inside.
------I love the north eastern NC. BBQ with the cole slaw on top of the meat. OH MY, now I am a thinking of Pig pickens and Peanut boils.--------- Collard greens and ham with red eye gravy.
Going to have to experiment with a bottle of Apple Cider Vineger also, never tried that or would have thought to try it had you not mentioned it.
Temperature at around 7 am is about 67 degrees ------I wonder how the rest of the country is doing with Temps.
still in the triple didgets and a million or more without power ?