My guess would be the same as yours...most likely varroa.
Quote Originally Posted by RichardsonTX View Post
I don't think I'll ever go treatment free again
Just so you understand...I don't advise people to treat or not. I recommend that they make the an educated choice and understand the potential consequences of either.
I do advocate using a repeatable method of testing...no matter which course you choose. That way you can make a better evaluation of any losses.