My first big question is finding the proper calculation for having multiple outlets? I've read a lot of information and some say you have to take into account the horizontal and some say no. I plan on putting valves before each return to regulate flow for each tank.
The calculation I have come up with is about 15 feet. That's a 5ft lift to the top with 3 tees, a few elbows and about 17 feet of 1in pipe total. Does that seem about right to plan a pump size off of?