What type of water to use with a laser cutter.
Never use tap water in your laser cutter it will cause problems for the laser tube.
Based off our research you shouldn't use anything other than distilled water. It looks like plane distilled water is the best thing to use at the moment. We are currently conducting new research into additives to help improve the cleanliness of the water over its lifetime.
An interesting side note. It looks the more conductivity the water carries the worse it is for your machine.