Air Tank supply isn't enough

i currently run 2 blitzlifts 337 into a 6 gallon tank with 1/2 ports and 1/2 valves, going to 145 psi. One time up in the front or back sucks enough pressure out my compressors kick on. So of course more then one time down and up sucks me down to almost no pressure. It takes my compressors about 2 minutes to fill back up. So my question is, if i go to 2 tanks, one for the front and one for the back will this help me out with being able to hit my switches more? More importantly if i go with 2 three gallon tanks or 2 five gallon tanks, which ones would be easier on my compressor. Or which ones can my compressors fill up quicker. I dont want to go any fast up or down its already way to fast, i only say that cause if i get 2 three gallon tanks its more pressure packed into a smaller area resulting in air wanting to escape faster. Any info, or personal experiences would be helpful. Also i dont want to change my compressors or go to a belt driven, or change the size of my lines or valves. I just want to change to 2 tanks. thanks