WD20000A4NC Raid 5 - How to Upgrade to 4 x 6TB from 1Tb

Anyone done anything like this before… the NAS works briliantly at the moment?

Will buy WD Red EFAX 6Tb hard drives but I really don’t want to get something that doesn’t work.

Currently has 4 x 1tb WD Green units in it, original fitment.

Raid 5

2.68 TB size

86% full

389.77gb free space

1TB drives x 4

WDC WD10EARS-00Y5B1 x 2

WDC WD10EARS-00L5B1 x 2

Hope someone can help…

I am in Australia, not that this should matter.