A new customer is having her fiberglass pool redone. The pool was green and nasty and the guy quoting the work said to drain it and they will get started in a few weeks. It's fiberglass clued to old concrete. Anyway, my sump pump was coated in fiberglass after the drain. Will DE filter be OK after a thorough cleaning? Or do I need to replace the grids? Or clean, fill pool, run 24 hours, clean and replace grids? thoughts? fiberglass seems a nasty business :/ thanks