I lose water pressure after I flush the toilet. I have well water and never had this problem before. I noticed it about 2 weeks. We flush the toilet and when we go to wash our hands the water in the sink comes out very low and then nothing. I checked the gauge on the tank and it reads 30psi. I turned the tank switch off and the tank gauge does not move. I turn the switch back on and still nothing it is always at 30-35 psi. The toilet tank fills very slowly and after it is filled the sink will start working again. Please help. Thanks Tom

Sounds like your pressure tank is "water logged" you need to drain it completely, and then take an air tank and recharge the thing.. depending on the size of your tank, it should read between 30 to 45 psi.. after you do that, open your main supply inlet and then refill your tank... hope this helps... it's mainly for tanks with a "bladder" in the bottom... just "old school".. johnjohn1

You say;
it is always at 30-35 psi. Does the pump run up to 30/35 PSI and then shut down or does it just keeps on running? Can you furnish more details? Type of pump. Depth of well, etc. Back to you, Tom

Welll guy just left... tells me that my water level is at 394 and pump is somewhere between 400-425 ft below ground.said I am running out of water... I also have a toilet that keep running and a leak under kitchen sink.

I can't help with a lowered water table but I can with the toilet and sink. Let's do the potty first.
Where's the leak Is it the ballcock thatn runs or is it the flapper leaking into the bowl? Let me know, Tom

my water level is at 394 and pump is somewhere between 400-425 ft

You may or may not be running out of water but the well is not causing the problem you are having with the toilet and the faucet.

What type of well tank do you have, a bladder tank or a galvanized pressure tank?

You pressure setting are a little low. You also probably have sand or debris blocking the toilet fill valve or ball cock.

Any chance of lowering the pump?