We have a fairly new (may 06) IG pool /spa and when I cleaned the filter this weekend it had a ton of white milk dust similar to when the pool surface was brand new and the marcite was curing. I have not fully tested the water @ PS (still waiting on Ben's kit .....all summer now ), but the Ph and simple tests from my small test kit were close to OK. (Ph7.7, Cl 3.0, TA 80).

I am scared the finish is failing......is it normal for some of the finish to make dust and be seen when filter is being cleaned?

I also notice the pressure drop didn't go down the the typical level post filter clean, so I am planning on cleaning the filter again using the dish-washing detergent method tonight.