need to add perlite..

hey all . as my first grow is almost done ,im starting to think of my next grow.. i used mg soil .BUT after learning here, i picked up a bag of FFOF ,i plan to use . My question is ..
i can only find MG perlite, the bag says it has mg added .Can i flush the perlite to leach out the mg nutes before mixing to the FF .
I havent opened the FF bag ,do i even need to add perlite to the FF?
Thank all

That's the only MG product I happen to have left in the basement prior to going organic. The added chemical nutes in that perlite is very low, it can be washed out fairly easily b/c it's the powder portion not the granules.

nice ! thank you