Moisture control is a big deal. The best way to deal with it is an exhaust fan. A dehumidifier can make a small room really warm. Costco is selling an exhaust fan with a built in humidistat. That is a great way to go.
I tell this to everybody, but it seems a good reminder.... While you have things all taken apart, run a small PVC line through the wall to bring outside air into the skimmer. It will give you 0.1 or 0.3 points more pH, especially in the summer.
As far as the grinder sump goes, I had an assist pump in my fish room to bring water up to my sewer line. I trashed it in 4 years of water changes and skimmer cleanings. It wasn't the saltwater, it was the solids. You put at lot of solids into the system over the years, and eventually it plugs them up.