Species Identification

Since the 3? Symphysodon species can breed and produce fertile offspring, is there any point in trying to identify what species I have? I seem to recall from high school biology that that was the definition of a species, i.e. being able to reproduce fertile offspring, so aren't the Symphysodon variants just one species?

I am new to Discus and am curious to know if I have symphysodon discus, or aequifasciatus or whatever, simply because my reading tells me they come from different water conditions in the Amazon and I'd like to think I was providing them with a good home. I realise it probably makes little difference, and since mine are domestic bred, maybe it is pointless trying to say what kind they are?

Just a question out of interest. Not trying to challenge the classification as I'm sure more qualified people than me have spent a lot of time thinking about it.

Out of interest, what would you call these guys?
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