Helping a friend. They have an 18x36 in ground pool 5' deep. Still have slight cloudiness. We're told by pool store to change sand in filter. I am trying to convert them to bbb. I used my tf100 to test their water. Here are the results.
Sand filter pressure at 12 psi
Pool slightly cloudy. They were told to "filter aid" ? Help. I can't see anything obvious.