I had no idea that this was the case. Thanks for the heads up, but now I have to rethink this
I honestly wouldn't worry too much about it. If you're using a finer grain sand, yes, then you have an issue. But PFS is a large enough grain that it does not stay suspended in the water column at all. I use FairmontSantrol's AquaQuartz #20 grain and it has plenty of weight to stay on the bottom. Even if you have fish that root around the bottom, i.e. plecos or loaches, you'll be fine. Just rinse the sand well before adding, let it settle for a bit, fire up the filter and off you go. Now, I always turn my filters off before doing water changes, but beyond that, you should never worry about PFS messing up your filter.