does saltwater tank smell?

They do not smell any different then a freshwater. You cannot smell the salt. Maybe your friend need to take a bath?!
 
Mine salty doesn't smell at all, unless I am cleaning the skimmer cup. then it will clear the house its so nasty. But in general I would say that they had a problem with the tank.
 
If you stick your nose right over the water and sniff they do smell a little different than a f.w. set up but, it's not as stong and not unpleasant. Now, cleaning out your skimmer or removing a dead sponge ,"a stink that defies description."
 
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