Should i put in an overflow?

[gargoylenest]

I got a pierced 35gal aquarium, a IPEX pipe letting water in up to about1 inch from the surface of the display tank, topped with a strainer to prevent snails, fish etc to get in. Sump is able to contain the 1 inch of water in main display if pump stop working.
I see almost every tank setup being set with an overflow; is there any other advantage to that then limiting the amount of water to drain down in case of a pump failure?

Thanks for the help

PS.Sorry for my bad english.

 

[ucdcrew]

Surface skimming

 

[gargoylenest]

undeniably does a big difference since I installed one in.

 

[Jscwerve]

Is it drilled in the bottom, or the back?

 

[rbla51]

Surface skimming

they do make a nice little surface skimmer, Eheim,i have one on a planted tank