ummm...since no on has asked, have you measured the relative humidity in your safe to include the extreme highs and lows?
Maybe worth your while to check.
Most department stores sell inexpensive hydrometers that will show the relative humidity as well as showing the highest and lowest measurement.
Doug Wicklund, the senior curator at the NRA Firearms Museum, recommends 70 degrees and 50% humidity. But the key point he stresses is to maintain as stable an environment as possible.
I maintain around 35-70% humidity and have zero rust issues. If the humidity rises above 70% , I turn on a 25 watt incandescent light bulb that I wired to the inside of my safe. That 25watt bulb works just as well as a dedicated Golden Rod...and is a LOT less expensive.
The Golden Rod's only function is to raise the interior temperature slightly more than ambient temperature to prevent condensation. The Golden Rod
doesn't remove moisture, it just just keeps the items inside a little warmer so that moisture doesn't collect on your firearm's surfaces. At almost $50 for a product that doesn't actually reduce humidity (it is sold as a "dehumidifier" to be used to "remove humidity" from the inside of a gun safe), in my opinion, the Golden Rod is a rip off and a waste of money.
Remember that relative humidity is the ratio of how much water is in the air divided by how much water the air can hold at saturation. The denominator, the amount of water the air can hold at saturation can be changed by raising the temperature. Raising the temperature inside your safe keeps the moisture from condensing (think "dew") onto your gun's metal surfaces and creating rust.
http://www.nramuseum.org/media/940963/conservationinfo.pdf (see page 2)
Keep in mind that too little humidity can be detrimental to any wood on your firearms. Humidity levels that are too low can cause wood to dry, shrink and crack.