I keep my guns in the cellar in three large safes. My hunting guns are covered in a plastic sleeve which prevents rust from occuring.
The "toys" i.e pistols etc are just locked in the safe. In the last month, I have noticed quite a bit of rust having built up. I switched the dehumidifier on and left it running for 18 hours; just as well I checked the water bucket as it was close to full with 2 litres of water. I checked it again after another 18 hours and there was only a liter. Should I keep the dehumidifier running permanently or not?