really hard to say at this size, but base on the pics I'd say it might very well be a mac. is the black band at the end of the tail or right before it which means leaving a clear ban at the end of the tail.
I've never seen a rhom with a black band in the middle of the tail and clear band at the end of the tail. I really think it can very well be a mac.
take a look at the links below and see which one matches your fish http://opefe.com/maculatus.html http://opefe.com/rhombeus.html