Thank you for your response! I saw it this AM and took him to the emergency vet. They took a sample to see what it was and it was indeed a seroma. What they’re wondering is why? They think it might be from the micro chip that was placed. They did drain it and said it’s a 50/50 chance it’ll come back- and sure enough it has. So I’ll have to make an appointment with my vet- they talked about possible “surgery” to remove the chip and figure out what’s causing the leak. Seems aggressive – everything i read said seroma stake time to go down. Any thoughts?