Can I sequence 2 12v peltier cooler plates to be used with a 24v supply? My guess is yes, but why not check. Also, is it more efficient to use a few larger rated coolers, or a bunch of lower ones? I assume lower ones because heat removal will be easier, but the efficiency might not be the greatest. Looking for a balance. Finally, how good are peltiers at cooling water, I’m cooling around 20 oz of water, maybe more, which needs to be in the 40-50 degree Fahrenheit zone, or lower if easily doable, with a moderate heat load.