Curt couldn't get a definitive answer from them on this so I would guess yes it does.
Here's a few more stories that make me suspicious of it.
I also talked to someone who sold multi-pure filters and she tried to get independent testing results on alumina filters for fluoride. She couldn't find a thing so suspected yes alumnia or something formed from it leaches into the water.
And a friend who uses a royal Dalton filter for fluoride on her water tested extremely high after a year or so for aluminum in her hair. I'm suspicious of her filter although she didn't seem interested in investigating this further.
Curt had the aquaspace carafe filter made with just bone char...they will do this if you request it. I don't know what that means in terms of how much Fl makes it through but I told him it's still probably better than unfiltered.
btw...aluminia is used in many city water filtration system to flocculate out solids.
So if this is true that it's leaches Al then most of us are getting some no matter what.
Silica is supposed to help chelate out Aluminium although I've no idea how...simply one of those things I've read a few places with no supporting evidence.