I just purchased a home that is 75 yrs old. I do not know how old the well is. I has a 2" pipe and was told the depth is between 160' and 190. I've had two Well companies out to check it out. One says I need a new pump and one says I need a Well. I was raised on well water and know a little about wells. What happens is if I run the water at a faucet, spigot or flush one at a time it works ok. But if I do any of them at the same time the pressure drops to nothing. Turn all off and within 10-30 seconds and the pressure is ok. What type of test can I preform to see if the tank/bladder is keeping pressure or do I need a new well or pump?