It appears that 1000 gallons of pressurized storage requires ~90+ gallons of expansion tank volume. An Amtrol SX-160V plus an SX-40V appears to have worked for some here. Those items will cost $750+ shipped. I noticed the local menards has 119Gallon Water Worker well tanks on sale. A little research turns up 100psi max pressure, 200F max temp and a precharged pressure that would need to be adjusted (Schrader valve on tank for that). The Amtrols are rated for a slightly higher max temp and this is the only difference I can see. I am quite sure in my planned install the expansion tank will never see 200F. Any reason not to try the 119G well tank? If the bladder would fail wouldn't it still work as a non-bladder type expansion tank?