Quite possibly I'm out to lunch on this, but I was under the impression that
this handle is invalid - A. giganteum = Anthurium salviniae, a HUGE
indigenous birdsnest Anthurium with a pendent inflorescence. When hiking in
Pacific coast cloud forest I have occasionally encountered truly massive
individuals that had toppled off their perches. These buggers wud literally
flatten you if one were unlucky enough to be underneath them when they drop.
Your plants sound extremely impressive - do you know their origin?