What is the lifespan of a Marid?

I'm playing a genie warlock, who's family patron is a Marid. And for backstory purposes I wanting to know how long they live for

They're elementals, so I don't think they age.

Quote from SagaTympana >>

They're elementals, so I don't think they age.

 Ah. Okay that makes sense.  Thank you. 

Heya,they are often discribed as immortal beings!,not needing to eat ,sleep or drink nor do they age! 

They only die when slain! I believe the monster manual states it!

Is this for all types of genie or just marid?

All elementals, I believe. Typically anything from farther out than the Feywild/Shadowfell doesn't age, and even in those places you'll get a lot of ageless beings.

Elementals, fiends, celestials, and most fey unless otherwise noted (such as dryads who's lifespans are tied to their trees) tend to not age.