I would imagine it takes out some salt but if you think about the small amount of water going into even the largest of skimmers and the volume of water in the tank I doubt you would ever notice it.
Thanks guys, so the general view is that skimming does not remove salt fro the water. so would this work?
If I was to skim really wet all the time and remove lots of water (as much as possible, skimming as wet as possible) could i just top up with RO water alot and therefore reduce the need to salt mix RO as much.
Scientifically, yes it does remove some sodium and chloride from the water column... However the actual amount does not really dent the sg in the normal practice of running a fish tank.
Wet skimming vs dry skimming makes no difference in the amount of dissolved organics actually removed from the water column.