my most-used PC is also the first time I incorporated liquid cooling into the design. I used mostly EK parts, 3 X GTX 780s hydro classified, and - for the actual cooling - red EK fluid (the only choice at the time). Here's my question: recently I noticed that the level of coolant in the resevoir looked lower than it used to be. for the first time ever, inspiration struck and i took a sharpie and drew a mark at the water line. I kept checking back (really whenever I remembered... probably a couple times a week or so) for approx. a month. the level went down another ¾ of an inch (or so) in that time. i checked everywhere for a sign of a leak, iinside the PC and out, and found nothing. (the PC in question - btw - is running without a hiccup.) Where is the coolant going????? the only hypothesis i could come up with is that whatever makes the coolant red is separating from the plain water in the coolant and somehow t he red part is condensing.... I don't know. Dumb theory.