Clean the Filter!
Pressure doesn't change when you change substance, 120 PSI in water equals 120 PSI in air.
what should your psi be around in a inground swimming pool andt it hold 12,000 gallons of water
Typically you only need to backwash when your filter's PSI is double its starting PSI level. For example, mine starting PSI is between 7 and 12, so when it gets to between 15 and 20 PSI I'll backwash.
That depends on filter, pump and plumbing size. What else is plumbed into the system. Does it have a pool cleaner attached and how? All this is called or is referred to as the amount of head. Ken
about 2 psi. (0.5 psi / foot of depth)
you have to backwash your pooluntil it starts coming out clear at the end of the backwash hose about 3-4 miuntes
The psi on your pool pump indicates how much dirt there is in the filter, the cleaner the filter the lower the psi. normally when the filter is clean you wil have a low psi and as the filter gets dirtier it will rise. However if the psi suddenly becomes much lower then usual it may indicate a fault in the filtration is letting unfiltered water circulate back into the pool as in a torn filter cartridge.
For water, a 60 ft vertical change is equivalent to about 26 psi change. So if the pressure is 60psi at the bottom, it will be 34 psi at the top. See related link.
The cleaning schedules varies from filter to filter, but a general guideline on any swimming pool filter is to take a reading when the filter is clean, then clean the pool filter when the pressure rises about 10 psi.
Around 10 PSI if you have a 2 horsepower pump. It will vary, depending on the restrictions in the exit line. Pool Masters
The frequency of changing or cleaning your pool filters will depend on the kind you have. If you have the variety that uses sand, you should have it cleaned once a year, any more frequently and the filter may not work effectively. If you have a cartridge style with an indicator then a marking of 8 to 10 PSI is when it should be replaced.