Its basically a coin flip , it can work if done correctly. With the tank of your size you have a good chance of making it work.

What I recommend is adding them at once, that way neither one of them are established , which will lessen the chance of a fight.

If you already have one in your tank then I recommend you catching him/her , re-arrange the rock a bit, and then add them both together ( at night )

In my tank I have:

1 Sohal
1 yellow
1 purple
1 regal
1 atlantic blue

They get along good

HTH