I have had a recurring issue over the past couple months where I will clean my DE grids, recharge the DE, and within a day or two the pressure is too high for the pool vacuum to work. A couple of my grids are broken in the upper corner but there are no rips or anything in the grid fabric and no DE coming in via the returns. When I backwash and the recharge the DE it takes a matter of a few hours before the pressure is again too high. What would cause a clean filter to increase pressure so quickly and how can I fix it?