So probably a dumb question; Nearly everything on this boat is new to me. The sellers didn’t provide any worthy technical information. So it has a water manifold and two tanks. My question is, how do I know what position the Orange knobs have to be in to use a certain tank? There is a small point on the top side of one of the knobs but it doesn’t make sense as to whether it goes straight up or straight down. I’m just having trouble trying to winterize it making sure that I’m getting coolant through my lines from each tank. Any help is a big thank you