I am thinking about building an undercurrent system but I have a coupIe of questions that I need answered before I get stared. I have noticed that most of the undercurrent systems that I see online use 3-4" drain pipe connecting all of the containers yet the return pumps are usually only 1/2" or so. Would someone please explain to me why these systems are designed with such large connecting pipe if they are only drawing small amounts of water back to the control reservoir? Why 3” over 1 1/2” (or smaller)? Next, the systems that I have seen have a storage container that flows into the control reservoir through a float valve. I like this idea because I could keep the nutrient storage container in a different room. My question is, how do these systems chill the water in the storage container and the control res at the same time with one chiller? The only good solution that I can think of is to forget the storage res and find (or just build) a large flat control res (which could hold large volumes of chilled, nute water) and keep that unit in the other room. Am I missing something obvious?