Trophy Brooke trout

What is the length you would say is a trophy. Please don’t add 2 inches, I need to make a decision

Kept the fish-it was in a stocked pond-so no chance of reproducing.  And, summer temperatures warm enough probably wouldn't survive through the summer.  Breeder fish from a hatchery that they put in this year.  SE Minnesota

 Nice catch ifb  !! Released??  A few years ago I caught a 23” , 4lb brook trout on a Lake Michigan tributary while chasing some migratory rainbows. These Great Lake Brookies that run larger than inland fish are called Coasters . A splake will have a forked tail  where as a Coaster /Brook would have a straight tail , otherwise very similar. I would say an inland 15 “ is a trophy in WI.

Not fly fishing-but this 17 inch I think counts.  Was a stocked lake-so streams I would set the mark at 12 inches often.  Tributary to Great Lakes, 16

About 1977/78 I was fishing at what is known as Sheboygan North Point, a reef that projects into the lake. It's a spawning area for Browns and Brookies on Lake Michigan. Watched a guy land a pretty good fish while casting a blue/chrome Cleo. This fish was a tad over 8#. It wasn't until the fish died on the guys stringer that the colors started to come out and everyone realized it was a Brook Trout...a monster. He ran it up to Trilling Hardware and they weighed the fish on an official scale. They entered the fish in the annual Field & Stream contest and I believe it won.

It really depends where you live. If you're fishing smaller creeks in NY, Michigan or maybe Wisconsin, a 14-inch brook trout is a really good fish. If you're in eastern Quebec or anywhere in Atlantic Canada where you can find sea-run brookies, you don't even bother taking a picture of anything under 20 inches. 

15 inches