Houston owners of dual-fuel generators, specifically 8500 watt capacity, where & how do you get propane tanks for it?

Got a Westinghouse WGen9500DF Dual Fuel Portable Generator, and bought a used 33.5 lb. forklift-style tank from a buddy.

The hose that came with the generator won't fit the tank, and research tells me I'd do better with something other than a forklift tank.

I'm out near Willowbrook Mall, northwest of town, and there's a Rhino cage right around the corner, but those tanks are smaller than I want to use.

Seeking advice from someone with one of these fairly large generators.

Thanks!