Hmm, I've been growing this 'new' blue A. tortuosa for a while. Now it has an official marketing name 'Roscoe's Blue Tort'. Fun! Mind you, in German, Tort means 'cake'!
By the way, it will tend to brown-out in a high nitrate environment, otherwise is turns turquoise with blue tips and is a slow grower until it has a good base (like most A. tortuosa). There is, also, a pale grey tortuosa (may actually be A. horrida, as the tentacles are often out during the day) over here. Makes for an interesting contrast.
Ciao, er ... Aufwiedersehen,
Jamie V.
Cologne
Germany