Coolant leaking from back of engine?

Hello,

You might have one of the coolant hose leaking.
Overtime the hose will get brittle and rupture. Typically when a hose ruptures you will loose a lot of fluid in short period of time. Sometimes the clamps can brake and the hose will pop off.
There are couple of small coolant bypass hoses that connect to the back of the engine. They have a tendency to leak after few years.
It is little tricky to get to but can be done with little bit of patience.

Here are couple of helpful articles on coolant leak:

https://www.2carpros.com/articles/car-is-leaking-coolant

https://www.2carpros.com/articles/coolant-leak-symptoms

https://www.2carpros.com/articles/replace-radiator-hoses

Please let me know of any questions.

Thank you.