This has been said a few times but I think it needs to be said again:
Guys, I REALLY think the water plant puzzle is RANDOM or at any rate there is no specific pattern to it. Those who are searching for patterns are seriously going about it WRONG. Just try clicking a few levers and then go into one of the other rooms and click a few more and YOU WILL GET IT MUCH FASTER. I firmly believe this.
I was successful in less than 30 seconds abouut 5 or six clicks MAX. I did not read any theories and patterns at all. Once I found out the new clue had been released, I just went to Altador and went through it on my own by following my instincts. When I got into the water plant I just tried what seemed the most logical to me at the time.
I did the following:
When I got into the first room I didn't touch any of the wheel valves, only the switch.
The switch in the first room was down, I flipped it up.
The water moved to the other tank and I went through the door on the right.
In that room I flipped all the switches into the opposite positions of where they were. (two were up and one was down, I flipped the up ones to down and the down one to up.)
The tank filled with water.
THAT'S IT.
Then I got sent to the "you fixed it" page.
This convinces me that it is not complicated or anything you have to think about and puzzle out for too long. Just go into the rooms and flip some switches. Don't give yourself a migraine. If it doesn't work take a deap breath and flip some more stuff or something. Leave your maths homework out of it.
I don't think it's rocket science, really.
You want the moustache on or off? ...Too bad.