I would think not. Puffers in general find snails tasty (which might easily transfer to octos) and the puffer has a beak of its own. They are cute friendly fish but IMO are also a fish that needs it own environment. I got a small one from Ken right after TONMOCON II (we went further south and I visited him for day - I am his webmaster - but the puffer was shipped as we were flying home, not driving) and kept it in my 140 reef tank (only other fish being a mandarin). He seemed to do well for awhile but then stopped eating and eventually died. I know they can have problems with their beaks if there is not something to keep them filed down (there are forums on how to do this with a dremel but I am not up to that task) but my guy was still pretty young and I don't think that was his problem. definitely a great fish but not a candidate for an octo pal. Also, 29 gallons is too small even for a young one.