Hello, newbie here doing an owner/builder spa only. Wondering if anyone could recommend some considerations/must-have equipment for an in-ground spa. The spa is approx 11'x8' oval freeform shape. The spa will have a natural boulder waterfall going into spa and then a spillover on the front side that goes into a separate pool below. Specifically wondering number of pumps, size of pumps, size of heater, air-blower or no air-blower? Any recommendations that should be considered during the spa construction process. Thanks in advance for your help!