Buy loose or small packs of silica gel on here,i bought 10 x 25 gm bags for £3.00 (and it was freepost) along with 10 x organza bags for 10 pence. All you have to do is rip open one gel bag per organza bag and empty contents in.The entire thing takes less than 5 mins to do all 10 of them.
Result, i have TEN non toxic and power free dehumidifiers for less than 40 pence each that are way,way better than any comparable dehuimidifier on offer from manufacturers i`ve seen on here.
When the crystals turn green/blue it merely means that they are water saturated,just pour them from the bag onto an old foil tray and put them into the oven for an hour or so on 120 degrees until they return to the original orangey/pink and reuse as before.They are NON TOXIC so no need to worry about fumes etc, basically your just heating the water they`ve absorbed to evaporate it out of them.