We have a well and recently replaced our pressure tank. Our old tank was quite large and it was replaced with one that is quite small in comparison. Since the new tank was installed, we have noticed that we seem to lose water more often than we used to. We have a three story home, with the tank being on the bottom floor and the shower being on the top floor. If we have a shower and flush the toilet at the same time, the shower loses quite a bit of pressure for a few minutes and then it comes back. However, if we have a long shower (15 minutes), the pressure drops significantly to the point that we lose water. It then takes a long time for the pressure to build back up (we turn off the pump and wait). We have also noticed that there seems to be a slow drip of water coming from one of the pipes attached to the pressure tank (which has been happening since we got the new tank). We lost water today after only having one shower in the morning and a second shower 5 hours later. Nothing else other than flushing toilets and washing hands. So what we are wondering is if it is a problem with the pressure tank not holding its pressure when water is used for long periods (eg a long shower), or if it is a problem with our rate of water recovery for the well. Thanks!

Sounds liike a well recovery problem.
Did it do this with the old tank?

One thing. Do you have any filters or softeners on this system? How about a cut-off valve? I'm wondering about items which could have clogged when you did the change out on the tank.

We occasionally lost water with the old tank, but only on days where we used a lot of water... laundry, dishwasher, showers, etc. Only maybe once or twice per year. Now it happens on random days and doesn't seem to have anything to do with the amount of water we have used through the day. We do have a water filtration system and uv filter. We don't have a cut off valve... it was removed a few years ago as it wasn't working properly. The other thing we noticed today is that when the pressure got down to 20psi, we turned off the pump. After about an hour, when we went to turn the pump back on, the pressure had dropped to almost 0psi. One tap had been turned on for a few seconds after the pump was off, and that was it. After we turned the pump back on, the psi increased to around 35 right away but then dropped again to 30 after flushing the toilet once. We then turned off the pump again and left it for a few hours. This time, after not having used any water, it had dropped to around 27psi.

Let's get together on terms. A pressure tank is a large galvanized tank of 30 Gallons or more. A bladder tank is quite small and usually blue. If I understand your post you swapped a pressure tank for a bladder tank. Is that correct? What did you charge the bladder tanks PSI and what's the cut in point on the control box? Hoe old is your house and what material are your pipes Back to you, Tom

Yes, by that terminology, that is what we did - swapped a pressure tank for a bladder tank. The pressure tank was old and we had occasional problems so the plumber thought we should replace it. House is about 27 years old. Can't remember the name of the material for the pipes, but have been told that they aren't likely to rust... commonly used in newer homes. Can you tell me how to find the charge info and cut in point info? Only info I can see is that it says max pressure is 150 (written on tank), but the gauge only goes to 100psi. Just got home from work and checked the pressure and it is sitting at 50psi.

50 PSI sounds great.
Can you tell me how to find the charge info and cut in point info? The cutin/cut out point will be found on the control box. It will read 20/40, 30/50 etc, The lower number is your cut in point, You will charge your bladder tank at 2 PSI UNDER the cut in point AFTER you shut the pump off and open a cold water tap to bleed off the pressure. More questions? I'm as close as a click. Good luck, Tom

"We do have a water filtration system and uv filter"

Have you tried bypassing the filters to be sure they are not part of the problem?