I have found a few local places stock some stuff, lowes is decent and tsc is ok. Home Depot is useless as is home hardware. For some hard to find stuff I have used BRS. But lowes is my normal go to place if I'm getting lots, they are a bit cheaper then TSC. The most important thing is to plan it put exactly what you want, and then get extra cause it might not fit just how you want it, and don't forget to leave room to grow in the future when you decide you want to add a reactor or a pre filter or recirculating or who knows what. Valve for draining and cleaning is nice but not required, valve for filling is again nice, lots to think about