Filtering out metals?

[seilsel]

Manufacturers of chelating agents are pretty consistent with the idea that metals can be filtered out after a sequestrant has been applied with a DE filter or a sand filter + cellulose fiber.

Is this a total myth or is there some accuracy to it?

 

[JasonLion]

There is some truth. Metals combined with sequestrant will occasionally clump/crystalize into particles that can be caught by the filter. The problem is that there is no way to get this to happen consistently and reliably. The techniques that come closest to being reliable at getting metals to clump seem to lead to the metals depositing as stains just as often as clumping up and getting filtered out.