I recently purchased 3 pitcher plants. A Nepenthes rafflesiana, a Sarracenia "Dana's Delight", and a Sarracenia "Scarlet Belle". When they arrived (from shipment I assume), they didn't have any liquid in thier traps. Do they produce their own, or should I add a little distilled water to them? Also, a few of the mature traps were brownish and dried out. Is that part of the change of humidity? I don't see and critters in the pot or on the plants.