Who is the second best male long course meters swimmer of all time?

mark spitz

Yep

I think Biondi, Lochte, or Thorpe could also be in contention but agree with Spitz. I think he set 33 world records!

Here is a side thread, most dominant in one event. 
my vote is Adam Peaty

i thinks its micheal in the 200 IM ... (as a side note, as an ex discus thrower, Al Orter 4 consecutive olympic golds)

If it is dominance, then I agree with Peaty. 

I’m going with Buster Crabbe based on his Olympic success, AND his Hollywood silver screen career after his years of swimming competition.

Dan 

Second best of all time compares across eras. Another perspective is to think about who would have had a more prominent career had it not been for some contemporary superstar. For example, we would all think differently about László Cseh if it weren't for MP. He isn't the 2nd best of all time, but he was astoundingly good over a long career.