The Green Phantom Pleco is a strikingly beautiful pleco, which reaches a modest size of about 6". These fish inhabit rapidly flowing water, and while they're very adaptable in the aquarium, they do need high oxygen levels.
While males of this species may fight and bicker among themselves, as well as with other similar Ancistrus-like catfish, they generally do not harm each other, provided enough hiding spots and room is given. .

Two separate, very similar species are imported under the moniker "Green Phantom" and L200. They are superficially similar, with Hemiancistrus apparently being the much more common (top picture). The High Fin variant is apparently Baryancistrus.