Upgrading to Red Reefer 525 XL

[jtmoney528]

5 foot tank - I am upgrading so I figured this would be a perfect time to add a second tang because it will be a new environment for them. I currently have a CB yellow tang. What would you add? Purple is risky because of same genus. Would you go with a Kole?

I have:
Mystery Wrasse
Ornate Leopard Wrasse
Richmond Wrasse
Pair of clowns
Bicolor Foxface
Diamond Goby
Pair of fire gobies
Red Scooter Blenny
Coral Beauty

 

[slingfox]

I also have a RedSea 525. I have a small yellow tang right now and am also considering adding another tang. I am leaning towards Tomini or White Tale Bristletooth.