Liquid-cooled data centers are starting to see issues with water-based coolants becoming contaminated and degrading nearby infrastructure. "Normally it's a water-based fluid with some sort of mixture of either ethylene glycol or propylene glycol. You're seeing a big shift toward safer fluids — propylene glycol is preferred, since it's less toxic." "A bunch of different things can happen in the system. You see a lot of basic infrastructure wear. So when your pumps and seals wear, all of that…