As I read through this thread, I noticed a common misconception. It is not the size of the tank, but the size of the compressor that matters. And as for the compressor, it is not the "rated" horse power, but the actual output in cubic feet per minute at what PSI (pounds per square inch) that matters. Compressors sold by the big box stores and the like use the same methodology in rating the compressors as they do routers. THEY LIE! You can not plug a 3 or 5 horse power compressor into a 120V outlet! Read the fine print and see what the actual air output is.

I do a fair amount of blasting and with my pressure pot blaster, I have switched to crushed glass, imported from Canada. It works great and leave a surface ideal for paint. I am running a 5 hp Ingersol Rand compressor that will put put out 17 cubic feet per minute at 175 PSI This used 28 amps at 240 volts. and is wired to the breaker panel with number 8 wire. It is a short run or I would have upgraded the wire to number 6. I run a small carbide nozzle and use very fine grade grit.
CPeter