I know it sucks. I have had several dogs go down with hypoglycemia while training over the years. I even have had a couple while doing water work. That isn't fun. You think it wouldn't happen in the water but our lakes around here get in the 80's so it doesn't cool them down much. The only place you can go around here to work your dogs in the heat is a gravel pit. They are very deep and very cool. Now algea or crap like that in the water either. Good luck with your pup.