We have decided to build a pool. 18x36 vinyl rectangle. I know that I won't a pentair variable speed pump with pentair SWG. Polaris 280 with booster pump and sand filter. What I am not sure bout is the system controller. What is the best one for the money. How does it work And so forth. Also do I need two skimmers nd how many returns. Pool builder Saudi old be ok with on wide mouth skimmer and 2 returns not sure