My swag would be to add the crawfish to help the fish grow faster. I don't think that they will take away from your Sunfish predation issue. If the predatory fish are not growing that fast (hood RW) then I don't think having more food for them will be bad - including YOY sunfish.

Look at it from an engineering/math standpoint. How many predators do you have in there? How much weight do you expect them to put on this coming year? How many pounds of YOY fish will that take? Will there be enough YOY fish??

There obviously wasn't enough for them in 2015.

Once you do that drill, then make a decision on the crawfish.

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