I use a wipe solution of distilled H2O, few drops lavendar oil, few drops TTO, a tsp burt's bees apricot oil, and a squirt of baby soap (Aveeno). Honestly, I've never used plain water, but I've heard that you can have mold problems with wet wipes if they sit in the pail for too long. TTO helps as an antifungal to keep mold away. I use this solution because it is super easy to make and keep in a spray bottle, and it smells SOOO good. I know lots of people use plain water without any problems!