There are good mites like Springtails, but I don't think what you described were them. You need to soak him in a container that can be filled deep enough so the water level is up to his chin. Be sure its luke warm water. Clean his entire enclosure out and replace his substrate with new. Also soak any fake plants or furniture in really hot to scalding. De-chlorinated water. This way to rid the enclosure of the mites. This is probably why he has been getting in his water so much. His substrate is probably infested with them.