Question about replacing clownfish?

[MarkW]

I have a 120 gallon reef tank which had 2 Clownfish, Royal Gramma, Yellow Tang, and a Sailfin Tang. It also has some blue mushrooms. Unfortunately about a week ago I lost one of the Clownfish. One was very small, one big. The one I lost was the small dark colored clownfish which I believe is male. Is that correct?
My question, how can I safely replace this clownfish? These are false Percula. Will there were any problems with aggressiveness and as well do I have to worry about getting a female or male when I replace or will it choose the sex later? This has been a stable tank for around 4 years with lots of live rock and no anemone at this time.

 

[perrl]

I have a pair of true perc's. When my little male went carpet surfing I just purchased another small clown and added it to the tank after a 3 week QT. He was about half the size of my female and they set up an instant bond. Baby clownfish are sexless and will change into a male if a female is present.
I would get the smallest, healthiest fish you can find and after a QT put them together. With the size difference there shouldn't be any fighting.