need some input

[mark]

Have my sump and fuge in the same room as my furnace/HRV/HWT/panel and only corrosion noticed since the install in early 2006 is salt buildup and pitting on the return duct directly above the sump (return/skimmer area so bubbles) and on a fan motor directly above the fuge but all within about 2 feet of the water surface.

Nothing on the return duct a foot over from the sump, on the copper pipes with the HWT and AC, electrical or even cheap tools also in the room, but then room is probably more than 100sqft.

Am a little concerned went measuring out the salt from the dust cloud, so will do away from furnace and go slow.