I'm having the same results as Augie. Mine may be somewhat worse in that my craws are eliminating a lot of (most) vegetation I want to be here. My vis this year is even lower than last year, currently around 14-16" at best and my SMB don't seem to be making much of a dent in the population but I am completely riprapped around entire pond due to my extremely windy location with several deeper rock piles and structures.
I'm finding this is going to be a delicate balance for required forage for SMB without having turbidity issues.
I stocked 2 lbs of craws late summer of 2018 when I stocked my smallies and I can say for sure I wish I would have waited to get a little more size on the fish.
Last October I removed 21lbs of craws from my 5/8 ac pond and I don't think I hurt the craw population any.
I believe in my case, I may start trapping and removing the largest craws to try and get a handle on things.
If you want to add craws, proceed with caution-even the Northern variety can become a nuisance if conditions are right for their survival.

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