This just happened to me, floating thermometer broke in the mash. I am going to continue brewing it since the actual thermometer didnt break, just the outside layer of glass. It was a small hole. I strain my wort several times throughout the mashh, sparge, and at the end before transfering the chilled wort ito the ferm bucket. I will be able to see if any of the balls get through, but I doubt it since I use a very fine strainer, and if any pices of glass are in there small enought to get through the strainer they will be so small that they will be harmless and probably wont get sucked up during the transfer to ferm. also, if you spiphon your wort from your kettle, and leave the bottom, then the galls will likely have settled to the bottom and not get transferred.