My Basement Storage Plan

Just recharge your silica packs every 3 or 4 months to keep them working well.

Preheat an oven to 275 degrees Fahrenheit. Line a baking sheet with aluminum foil.
Lay the silica gel packets flat on the foil-lined baking sheet. For loose silica gel, spread the granules in a layer no more than 2 inches thick on the foil-lined baking sheet.
Place the baking sheet inside the preheated oven and bake for several hours. The amount of time varies between 1 to 12 hours depending on the thickness of the silica gel. A good general rule of thumb is baking for 1 ½ hours for every 30 ounces of silica gel.
Remove the baking sheet from the oven. Let the silica gel cool to room temperature on the baking sheet.
Store the cooled silica gel packet in an airtight container until you're ready to use it.
Read more : http://www.ehow.com/how_5035187_rec...ica-gel.html

And just how many remember to do that? Or why not just keep buying new ones? Or just move your coins out of such humid areas.
One of the big problems with moisture is the changing of temperatures. For example ever notice what happens on a car when you go from warm damp to cold. Moisture collects on the windows. This too happens on coins. Going back and forth in temperatures makes moisture collect on coins and this really makes them tone, tarnish, corrode, etc. For coins, or any metal, keep in as low a moist area as possible.
And so far I've never used any jel packs of any kind in over 60 years of collecting coins. No problems yet.

A tip for silica packs. My son worked at a furniture store. They constantly got in furniture that required assembling in the back room. It took him only a month and he got a Wal-mart type plastic bag STUFFED with them for me. All the store will do is throw them away anyway.

So try to see if a local store will save them for you instead of chucking them. All it took where he worked was to throw them in a box until the box was full.