If you wish to remain in the unit that you have recently received the 3 day notice to oay or quit, your option at the present time is to pay what is demanded so you can remain, vacate, or remain in the unit and face a likely unlawful detainer lawsuit.Another and best option if you do not want to pay the $50.00 water bill is to send documentation to the landlord showing that it was paid as well as $50.00. Possibly this will resolve the situation where the following month's rent can be reduced by the $50.00 that you pre-paid.