Whats a durable paint for back of aquarium?

[Jakesaw]

I want to upgrade my 10 to 20L. 

 

I painted my 10 gallon with the cheapest Home depot spray paint available.  I think it cost me a buck.  Sprayed on well but in 3 months, I've already got a good sized wide visible scratch on the back panel that lets light through the window.  I have no idea what could have scratched the paint as there is no activity behind the tank.  But it's an eyesore. 

 

I'm looking for a better paint for the 20L that can give a lifetime of protection on that back panel for black paint?  Or at least several years.  Any suggestions that has proven the test of time.

 

Thanks

[TrashTank]

Personally, I always use plastidip. Its peelable, but being a rubberized coating I've found it pretty durable. 

[MrP]

I've always used Rust-oleum oil based enamel. It's durable and has held up really well for me.