Macbook backup

I'm trying to set up an external Lacie HD for a wireless backup to my Macbook Pro via my Netgear R6300 router. The router recognizes the Lacie drive, but the Macbook does not see it. The router is wired to my PC and I also have an Imac set up wirelessly to the router. The Macbook is also set up wirelessly to the router. I can't understand why the Macbook won't see the Lacie. I am using Time Machine to do the backup.

The Imac and the Retina Macbook Pro both have OS X Mountain Lion.

Thanks for any help.

1. i don't think you can wirelessly back up to anything but a Time Capsule.

If there were a way to make that hard drive a file server, you might be able to.

Can you see the HDD on the network? Is it formatted for use with a mac?

The Lacie drive is formatted for the Mac. I am using it as backup for the Imac, but not wirelessly. I do see the Lacie on the network. The problem seesm to be doing the backup wirelessly and after all isn't that the main reason we have a router.