Formatting a drive for replacement into an Raid 5 Speed Q array

Hey everyone,

I haven’t been able to find a post on here about how to format a replacement drive before it is inserted into an existing raid 5 array.

I have a old speed Q (4 bay ) and one drive needs to be replaced.
When I got the unit it was already set up in RAID 5 for MAC so I’d like to keep it that way.
Blinking amber led on bottom drive tray.
Blinking red led warning light…left one of the 2 at the bottom.

I have a appropriate 2TB drive that needs to be erased and formatted to go in BUT I don’t know what format I should give it before inserting it.

Any help would be appreciated.