Have had a pool for 20 years and this year i have a problem i can't seem to conquer. These may be separate issues but here goes:
1- DE in pool. I replaced 4 of the 7 or 8 filter cartridges, 3 of which had obvious holes/tears in them but the DE is still making its way back into the pool. I cannot see any holes in the cartrdges not replaced. Using my polaris to vacumn the DE escapes the bag making the water cloudy so i tried to vacumn manually which creates second problem.
2- i close my main drain and skimmer furthest from pump and try to vacumn using skimmer closest to pump. i quickly lose suction as the pump loses its prime. When i remove vacumn pump primes up again which brings me to the third issue.
3- in the past my pump would operate at about 12-14 PSI and i would backwash at 18-20 never had issues. THis year my pump starts at around 20 and will increase to 25 psi until i backwash and then it goes back to 20 PSI. When the pump is running there are definitely air bubbles you can see in the pump basket, this was not the case in previous years. I loosen the pressure valve and air escapes for maybe up to 40 seconds before water shoots out of the valve but even then there is still air the pump basket window.
HOw can i tell where air is getting into the system and also how the DE is entering the pool?