after cleaning my DE

opened cleaned all grids put all back added de , increased pressure by 2 lbs ran a couple hrs , then this morning turned on and an overnight air leak allowwed filter to drain back so pump started priming . I believe when this happens it washes all the de off the grids . pressure dropped back to 10 down 2 psi . I think I have to open up and wash again then recharge . I think my air leak is on the multi valve and will tighten it up . question, is does the de wash off when air leak happens ?