Tried to install El Capitan on second hard drive, partition greyed out?

I can do first aid, erase and unmount,, but I can't partition

EDIT: http://ift.tt/20ZhgE9 If I try to install os x on it it says "A GUID partition Table (GPT) partitioning scheme is required. Quit the installer to restart your computer and try again.

submitted by /u/rapzeh76
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