How long until a hydrocele goes away after hernia repair?

It depends!: In order to answer the question, you'd have to know where it was, whether it was the first one, how big it was, and how long you had it before the operation. There are many factors! the good news is that seromas do go away, although sometimes we need to treat them.

Clarify: I am not sure what you are referring to when you talk about hydroelectric after surgery. You may mean a seroma which is a fluid collection that normally occurs after surgery. That will go away in 2-4 weeks. A hero else is a different condition from a hernia and usually requires surgical repair.