the honey came from a trusted source, I dont think it was the honey that was the problem I think the problem was heating the honey with water. I read an article in one of the bee magazines, I dont remember wich one cause I get them all, anyways it was by ross conrad and in it he said there is some kind of reaction that can happen when you heat honey and water. I fed some of the same honey still capped in the frame with no bad results. I think when feeding honey that is the way to go just drop in capped frames.